WO2025211697A1

WO2025211697A1 - Method and apparatus for random access in wireless communication system

Info

Publication number: WO2025211697A1
Application number: PCT/KR2025/004234
Authority: WO
Inventors: Zhongfeng ZHANG; Qi XIONG; Nan Qu; Feifei SUN; Bin Yu
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2024-04-03
Filing date: 2025-04-01
Publication date: 2025-10-09
Anticipated expiration: 2026-10-03

Abstract

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. A method performed by a user equipment (UE) in a wireless communication system is provided. The method comprises receiving, from a base station, configuration information including first information associated with a set of first signals and second information associated with a set of second signals and transmitting, to the base station, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs), wherein the one or more valid ROs are based on the first information and the second information.

Description

METHOD AND APPARATUS FOR RANDOM ACCESS IN WIRELESS COMMUNICATION SYSTEM

The disclosure relates to wireless communication technologies, and more particularly, to a method and apparatus for random access in a wireless communication system.

5G mobile communication technologies define broad frequency bands such that high transmission rates and new services are possible, and can be implemented not only in “Sub 6GHz” bands such as 3.5GHz, but also in “Above 6GHz” bands referred to as mmWave including 28GHz and 39GHz. In addition, it has been considered to implement 6G mobile communication technologies (referred to as Beyond 5G systems) in terahertz bands (for example, 95GHz to 3THz bands) in order to accomplish transmission rates fifty times faster than 5G mobile communication technologies and ultra-low latencies one-tenth of 5G mobile communication technologies.

At the beginning of the development of 5G mobile communication technologies, in order to support services and to satisfy performance requirements in connection with enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communications (URLLC), and massive Machine-Type Communications (mMTC), there has been ongoing standardization regarding beamforming and massive MIMO for mitigating radio-wave path loss and increasing radio-wave transmission distances in mmWave, supporting numerologies (for example, operating multiple subcarrier spacings) for efficiently utilizing mmWave resources and dynamic operation of slot formats, initial access technologies for supporting multi-beam transmission and broadbands, definition and operation of BWP (BandWidth Part), new channel coding methods such as a LDPC (Low Density Parity Check) code for large amount of data transmission and a polar code for highly reliable transmission of control information, L2 pre-processing, and network slicing for providing a dedicated network specialized to a specific service.

Currently, there are ongoing discussions regarding improvement and performance enhancement of initial 5G mobile communication technologies in view of services to be supported by 5G mobile communication technologies, and there has been physical layer standardization regarding technologies such as V2X (Vehicle-to-everything) for aiding driving determination by autonomous vehicles based on information regarding positions and states of vehicles transmitted by the vehicles and for enhancing user convenience, NR-U (New Radio Unlicensed) aimed at system operations conforming to various regulation-related requirements in unlicensed bands, NR UE Power Saving, Non-Terrestrial Network (NTN) which is UE-satellite direct communication for providing coverage in an area in which communication with terrestrial networks is unavailable, and positioning.

Moreover, there has been ongoing standardization in air interface architecture/protocol regarding technologies such as Industrial Internet of Things (IIoT) for supporting new services through interworking and convergence with other industries, IAB (Integrated Access and Backhaul) for providing a node for network service area expansion by supporting a wireless backhaul link and an access link in an integrated manner, mobility enhancement including conditional handover and DAPS (Dual Active Protocol Stack) handover, and two-step random access for simplifying random access procedures (2-step RACH for NR). There also has been ongoing standardization in system architecture/service regarding a 5G baseline architecture (for example, service based architecture or service based interface) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) for receiving services based on UE positions.

As 5G mobile communication systems are commercialized, connected devices that have been exponentially increasing will be connected to communication networks, and it is accordingly expected that enhanced functions and performances of 5G mobile communication systems and integrated operations of connected devices will be necessary. To this end, new research is scheduled in connection with eXtended Reality (XR) for efficiently supporting AR (Augmented Reality), VR (Virtual Reality), MR (Mixed Reality) and the like, 5G performance improvement and complexity reduction by utilizing Artificial Intelligence (AI) and Machine Learning (ML), AI service support, metaverse service support, and drone communication.

Furthermore, such development of 5G mobile communication systems will serve as a basis for developing not only new waveforms for providing coverage in terahertz bands of 6G mobile communication technologies, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), array antennas and large-scale antennas, metamaterial-based lenses and antennas for improving coverage of terahertz band signals, high-dimensional space multiplexing technology using OAM (Orbital Angular Momentum), and RIS (Reconfigurable Intelligent Surface), but also full-duplex technology for increasing frequency efficiency of 6G mobile communication technologies and improving system networks, AI-based communication technology for implementing system optimization by utilizing satellites and AI (Artificial Intelligence) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technology for implementing services at levels of complexity exceeding the limit of UE operation capability by utilizing ultra-high-performance communication and computing resources.

A method performed by a user equipment (UE) in a wireless communication system is provided. The method comprises receiving, from a base station, configuration information including first information associated with a set of first signals and second information associated with a set of second signals and transmitting, to the base station, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs), wherein the one or more valid ROs are based on the first information and the second information.

A method performed by a base station in a wireless communication system is provided. The method comprises transmitting, to a user equipment (UE), configuration information including first information associated with a set of first signals and second information associated with a set of second signals and receiving, from the UE, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs), wherein the one or more valid ROs are based on the first information and the second information.

A user equipment (UE) in a wireless communication system is provided. The UE comprises a transceiver and a controller coupled with the transceiver and configured to receive, from a base station, configuration information including first information associated with a set of first signals and second information associated with a set of second signals, and transmit, to the base station, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs), wherein the one or more valid ROs are based on the first information and the second information.

A base station in a wireless communication system is provided. The base station comprises a transceiver and a controller coupled with the transceiver and configured to transmit, to a user equipment (UE), configuration information including first information associated with a set of first signals and second information associated with a set of second signals, and receive, from the UE, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs), wherein the one or more valid ROs are based on the first information and the second information.

In order to illustrate the technical schemes of the embodiments of the disclosure more clearly, the drawings of the embodiments of the disclosure will be briefly introduced below. Apparently, the drawings described below only refer to some embodiments of the disclosure, and do not limit the disclosure. In the drawings:

FIG. 1 illustrates a schematic diagram of an example wireless network according to some embodiments of the disclosure;

FIGS. 2A illustrates example wireless transmission and reception paths according to some embodiments of the disclosure;

FIG. 2B illustrates example wireless transmission and reception paths according to some embodiments of the disclosure;

FIG. 3A illustrates an example user equipment (UE) according to some embodiments of the disclosure;

FIG. 3B illustrates an example gNB according to some embodiments of the disclosure;

FIG. 3C illustrates a schematic diagram of a 4-step random access procedure according to some example embodiments of the disclosure;

FIG. 4 illustrates a flowchart of a method performed by a UE in a wireless communication system according to some example embodiments of the disclosure;

FIG. 5 illustrates schematic diagrams of transmission periodicity of SSB burst (first-type SSB burst and/or second-type SSB burst) according to some example embodiments of the disclosure;

FIG. 6 illustrates a schematic diagram of transmission periodicity of SSB burst (first type SSB burst and/or second type SSB burst) according to some example embodiments of the disclosure;

FIG. 7 illustrates a schematic diagram of a time domain offset according to some example embodiments of the disclosure;

FIG. 8 illustrates a schematic diagram of a time domain offset according to some example embodiments of the disclosure

FIG. 9 illustrates a schematic diagram of an SSB-RO (SSB to RO) mapping according to some example embodiments of the disclosure;

FIG. 10 illustrates a schematic diagram of an SSB-RO mapping according to some example embodiments of the disclosure;

FIG. 11A illustrates a schematic diagram of an SSB-RO mapping according to some example embodiments of the disclosure;

FIG. 11B illustrates a schematic diagram of an SSB-RO mapping according to some example embodiments of the disclosure;

FIG. 12 illustrates a schematic diagram of an SSB-RO mapping according to some example embodiments of the disclosure;

FIG. 13 illustrates a flowchart of a method performed by a UE according to some example embodiments of the disclosure;

FIG. 14 illustrates a flowchart of a method performed by a base station according to some example embodiments of the disclosure;

FIG. 15 illustrates a block diagram of a configuration of a first node (e.g., UE) as a scheduled node according to some example embodiments of the disclosure;

FIG. 16 illustrates a block diagram of a configuration of a second node (e.g., a base station) as a scheduling node according to some embodiments of the disclosure.

In order to make the purpose, technical schemes and advantages of the embodiments of the disclosure clearer, the technical schemes of the embodiments of the disclosure will be described clearly and completely with reference to the drawings of the embodiments of the disclosure. Apparently, the described embodiments are a part of the embodiments of the disclosure, but not all embodiments. Based on the described embodiments of the disclosure, all other embodiments obtained by those of ordinary skill in the art without creative labor belong to the protection scope of the disclosure.

Before undertaking the DETAILED DESCRIPTION below, it can be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term “couple” and its derivatives refer to any direct or indirect communication between two or more elements, whether or not those elements are in physical contact with one another. The terms “transmit,” “receive,” and “communicate,” as well as derivatives thereof, encompass both direct and indirect communication. The terms “include” and “include,” as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive, meaning and/or. The phrase “associated with,” as well as derivatives thereof, means to include, be included within, connect to, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The term “controller” means any device, system or part thereof that controls at least one operation. Such a controller can be implemented in hardware or a combination of hardware and software and/or firmware. The functionality associated with any particular controller can be centralized or distributed, whether locally or remotely. The phrase “at least one of,” when used with a list of items, means that different combinations of one or more of the listed items can be used, and only one item in the list can be needed. For example, “at least one of: A, B, and C” includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C. For example, “at least one of: A, B, or C” includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A, B and C.

Furthermore, in the description of the example embodiments of the disclosure, “/”, when used between parallel items, may means “and/or”. For example, “A/B” may mean A and/or B.

Moreover, various functions described below can be implemented or supported by one or more computer programs, each of which is formed from computer-readable program code and embodied in a computer-readable medium. The terms “application” and “program” refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, related data, or a portion thereof adapted for implementation in a suitable computer-readable program code. The phrase “computer-readable program code” includes any type of computer code, including source code, object code, and executable code. The phrase “computer-readable medium” includes any type of medium capable of being accessed by a computer, such as Read-Only Memory (ROM), Random Access Memory (RAM), a hard disk drive, a Compact Disc (CD), a Digital Video Disc (DVD), or any other type of memory. A “non-transitory” computer-readable medium excludes wired, wireless, optical, or other communication links that transport transitory electrical or other signals. A non-transitory computer-readable medium includes media where data can be permanently stored and media where data can be stored and later overwritten, such as a rewritable optical disc or an erasable memory device.

Terms used herein to describe the embodiments of the disclosure are not intended to limit and/or define the scope of the present invention. For example, unless otherwise defined, the technical terms or scientific terms used in the disclosure shall have the ordinary meaning understood by those with ordinary skills in the art to which the present invention belongs.

It should be understood that “first”, “second” and similar words used in the disclosure do not express any order, quantity or importance, but are only used to distinguish different components. Similar words such as singular forms “a”, “an” or “the” do not express a limitation of quantity, but express the existence of at least one of the referenced item, unless the context clearly dictates otherwise. For example, reference to “a component surface” includes reference to one or more of such surfaces.

As used herein, any reference to “an example” or “example”, “an implementation” or “implementation”, “an embodiment” or “embodiment” means that particular elements, features, structures or characteristics described In combination with the embodiment is included in at least one embodiment. The phrases “in one embodiment” or “in one example” appearing in different places in the specification do not necessarily refer to the same embodiment.

As used herein, “a portion of” something means “at least some of” the thing, and as such may mean less than all of, or all of, the thing. As such, “a portion of” a thing includes the entire thing as a special case, i.e., the entire thing is an example of a portion of the thing.

As used herein, the term “set” means one or more. Accordingly, a set of items can be a single item or a collection of two or more items.

In the disclosure, to determine whether a specific condition is satisfied or fulfilled, expressions, such as “greater than/larger than” or “less than/smaller than” are used by way of example and expressions, such as “greater than or equal to” or “less than or equal to” are also applicable and not excluded. For example, a condition defined with “greater than or equal to” may be replaced by “greater than” (or vice-versa), a condition defined with “less than or equal to” may be replaced by “less than” (or vice-versa), etc.

It will be further understood that similar words such as the term “include” or “include” mean that elements or objects appearing before the word encompass the listed elements or objects appearing after the word and their equivalents, but other elements or objects are not excluded. Similar words such as “connect” or “connected” are not limited to physical or mechanical connection, but can include electrical connection, whether direct or indirect. “Upper”, “lower”, “left” and “right” are only used to express a relative positional relationship, and when an absolute position of the described object changes, the relative positional relationship may change accordingly.

The various embodiments discussed below for describing the principles of the disclosure in the patent document are for illustration only and should not be interpreted as limiting the scope of the disclosure in any way. Those skilled in the art will understand that the principles of the disclosure can be implemented in any suitably arranged wireless communication system. For example, although the following detailed description of the embodiments of the disclosure will be directed to LTE and/or 5G communication systems, those skilled in the art will understand that the main points of the disclosure can also be applied to other communication systems with similar technical backgrounds and channel formats with slight modifications without departing from the scope of the disclosure. The technical schemes of the embodiments of the present application can be applied to various communication systems, and for example, the communication systems may include global systems for mobile communications (GSM), code division multiple access (CDMA) systems, wideband code division multiple access (WCDMA) systems, general packet radio service (GPRS) systems, long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, universal mobile telecommunications system (UMTS), worldwide interoperability for microwave access (WiMAX) communication systems, 5th generation (5G) systems or new radio (NR) systems, etc. In addition, the technical schemes of the embodiments of the present application can be applied to future-oriented communication technologies.

Hereinafter, the embodiments of the disclosure will be described in detail with reference to the accompanying drawings. It should be noted that the same reference numerals in different drawings will be used to refer to the same elements already described.

The text and drawings are provided as examples only to help readers understand the disclosure. They are not intended and should not be interpreted as limiting the scope of the disclosure in any way. Although certain embodiments and examples have been provided, based on the content disclosed herein, it will be apparent to those skilled in the art that changes may be made to the illustrated embodiments and examples without departing from the scope of the disclosure.

In order to meet the increasing demand for wireless data communication services since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also called “Beyond 4G networks” or “Post-LTE systems”.

In order to achieve a higher data rate, 5G communication systems are implemented in higher frequency (millimeter, mmWave) bands, e.g., 60 GHz bands. In order to reduce propagation loss of radio waves and increase a transmission distance, technologies such as beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antenna, analog beamforming and large-scale antenna are discussed in 5G communication systems.

In addition, in 5G communication systems, developments of system network improvement are underway based on advanced small cell, cloud radio access network (RAN), ultra-dense network, device-to-device (D2D) communication, wireless backhaul, mobile network, cooperative communication, coordinated multi-points (CoMP), reception-end interference cancellation, etc.

In 5G systems, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) as advanced coding modulation (ACM), and filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies have been developed.

According to some aspects of the disclosure, a method performed by a user equipment (UE) in a wireless communication system is provided. The method includes: receiving configuration information, wherein the configuration information includes first information related to a set of first downlink physical signals and second information related to a set of second downlink physical signals; and transmitting a random access preamble based on one or more valid random access channel (RACH) occasions (ROs), wherein the one or more valid ROs are determined based on the first information and the second information.

In combination with one or more aspects of the method performed by the UE described above, for example, the configuration information further includes: first ratio information indicating a number of first downlink physical signals mapped to one RO; and second ratio information indicating a number of second downlink physical signals mapped to one RO.

In combination with one or more aspects of the method performed by the UE described above, for example, the configuration information further includes at least one of: second indication information indicating indexes of first downlink physical signals in the set of first downlink physical signals; third indication information indicating ROs associated with the first downlink physical signals or the second downlink physical signals; information about time domain resources of the set of second downlink physical signals; information about frequency domain resources of the set of second downlink physical signals; or a second TDD uplink and/or downlink configuration.

In combination with one or more aspects of the method performed by the UE described above, for example, the information about time domain resources of the set of second downlink physical signals includes at least one of: a transmission periodicity of the set of second downlink physical signals; a time domain offset indicating a time domain offset of the set of second downlink physical signals with respect to the set of first downlink physical signals or a time domain reference point; a number of the set of second downlink physical signals; a transmission indication information of the set of second downlink physical signals, wherein the transmission indication information indicates indexes of transmitted second downlink physical signals in a third transmission periodicity, and/or indexes of non-transmitted second downlink physical signals; the third transmission periodicity, wherein at least one first downlink physical signal and at least one second downlink physical signal are transmitted in the third transmission periodicity; a periodicity of the third transmission periodicity; or a transmission pattern of the second downlink physical signals, wherein the transmission pattern indicates an index of a first symbol of candidate second downlink physical signals in a time unit.

In combination with one or more aspects of the method performed by the UE described above, for example, the configuration information further includes first configuration information related to a first random access and second configuration information related to a second random access, wherein the first configuration information is associated with the set of first downlink physical signals and the second configuration information is associated with the set of second downlink physical signals.

In combination with one or more aspects of the method performed by the UE described above, for example, the second configuration information includes at least one of: a configuration index; a mapping ratio of downlink physical signals to ROs, the mapping ratio indicating a number of ROs to which each downlink physical signal is mapped, the downlink physical signals including first downlink physical signals and/or a second downlink physical signals; a period related to random access; a number of frequency multiplexed ROs; a frequency domain starting position of ROs; a root sequence index; a number of preambles; or a power-related configuration.

In combination with one or more aspects of the method performed by the UE described above, for example, all or part of the content of the second configuration information is the same as all or part of the content of the first configuration information.

In combination with one or more aspects of the method performed by the UE described above, for example, the second configuration information and the first configuration information are the same with respect to at least one of: a configuration index; a number of frequency multiplexed ROs; a frequency domain starting position of ROs; a root sequence index; a number of preambles; or a power-related configuration.

In combination with one or more aspects of the method performed by the UE described above, for example, the valid ROs includes first valid ROs associated with a first random access and/or second valid ROs associated with a second random access.

In combination with one or more aspects of the method performed by the UE described above, for example, the set of first downlink physical signals includes first downlink physical signals and the set of second downlink physical signals includes second downlink physical signals, and wherein an RO in a random access time unit is a valid RO in case that at least one of the following conditions is satisfied: the RO is within uplink symbols determined based on at least one of a first time division duplex (TDD) uplink and/or downlink configuration or a second TDD uplink and/or downlink configuration; the RO does not precede the first downlink physical signal and/or the second downlink physical signal in the random access time unit, and/or the RO is at least N1 symbols after a last downlink symbol in the random access time unit and/or a last symbol of the first downlink physical signal and/or the second downlink physical signal in the random access time unit; a first symbol of the RO is at least N2 symbols after a last symbol determined based on the second TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal; the first symbol of the RO is at least N3 symbols after the last downlink symbol determined based on the second TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal, and N4 symbols before the last downlink symbol determined based on the first TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal; the first symbol of the RO is at least N5 symbols after the last downlink symbol determined based on the second TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal, and N6 symbols before the last downlink symbol determined based on the first TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal; or the first symbol of the RO is at least N7 symbols after the last downlink symbol determined based on the second TDD uplink and/or downlink configuration and/or a last SSB symbol, and before N8 symbols after the last downlink symbol determined based on the first TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal.

In combination with one or more aspects of the method performed by the UE described above, for example, transmitting a random access preamble based on one or more valid ROs includes: determining an available RO from the one or more valid ROs based on a mapping of first downlink physical signals and/or second downlink physical signals to ROs and a received first downlink physical signal and/or a received second downlink physical signal; and transmitting the random access preamble in the available RO.

In combination with one or more aspects of the method performed by the UE described above, for example, the mapping of first downlink physical signals and/or second downlink physical signals to ROs includes one or more of the following: the first downlink physical signals are mapped to first valid ROs among first ROs associated with a first random access, and the second downlink physical signals are mapped to remaining ROs among the first ROs other than the first valid ROs, the second downlink physical signals are mapped to first valid ROs corresponding to a third index group, wherein the third index group is based on at least one of a first index group determined based on indication information of the first downlink physical signals transmitted in the first downlink physical signals or a second index group determined based on indication information of the second downlink physical signals transmitted in the second downlink physical signals; the second downlink physical signals are mapped only to second valid ROs, wherein the resources of the second valid ROs are different from that of the first valid ROs; in case that the resources of the second valid ROs partially overlaps with the resources of the first valid ROs, the second downlink physical signals are mapped only to ROs not overlapping with the first valid ROs among the second valid ROs; the second downlink physical signals are mapped to the remaining ROs other than the first valid ROs among the first ROs and the first valid ROs corresponding to the third index group; or the second downlink physical signals are mapped to the first valid ROs corresponding to the third index group and the second valid ROs.

In combination with one or more aspects of the method performed by the UE described above, for example, the third index group is determined based on the first configuration information and/or second indication information included in the configuration information, wherein the second indication information indicates indexes of first downlink physical signals in the set of first downlink physical signals.

In combination with one or more aspects of the method performed by the UE described above, for example, the method further includes receiving feedback information for the random access preamble, including at least one of: detecting the feedback information using a first radio network temporary identifier (RNTI), the first RNTI includes at least one of an RNTI determined based on ROs for transmitting the random access preamble, a cell radio network temporary identifier (C-RNTI), or an RNTI configured for the UE for receiving the feedback information; or receiving the feedback information in a control resource set (COREST) and/or search space, wherein the COREST and/or search space is specific to a UE supporting network energy saving, or specific to network energy saving random access, or specific to a UE transmitting the random access preamble in ROs configured for a second random access.

According to some aspects of the disclosure, a method performed by a base station in a wireless communication system is provided. The method includes: transmitting configuration information to a user equipment (UE), wherein the configuration information includes first information related to a set of first downlink physical signals and second information related to a set of second downlink physical signals; and receiving a random access preamble based on valid random access channel (RACH) occasions (ROs), wherein the valid ROs are determined based on the first information and the second information.

In combination with one or more aspects of the method performed by the base station described above, for example, the configuration information further includes: first ratio information indicating a number of first downlink physical signals mapped to one RO; and second ratio information indicating a number of second downlink physical signals mapped to one RO.

In combination with one or more aspects of the method performed by the base station described above, for example, the configuration information further includes at least one of: second indication information indicating indexes of first downlink physical signals in the set of first downlink physical signals; third indication information indicating ROs associated with the first downlink physical signals or the second downlink physical signals; information about time domain resources of the set of second downlink physical signals; information about frequency domain resources of the set of second downlink physical signals; or a second TDD uplink and/or downlink configuration.

In combination with one or more aspects of the method performed by the base station described above, for example, the information about time domain resources of the set of second downlink physical signals includes at least one of: a transmission periodicity of the set of second downlink physical signals; a time domain offset indicating a time domain offset of the set of second downlink physical signals with respect to the set of first downlink physical signals or a time domain reference point; a number of the set of second downlink physical signals; a transmission indication information of the set of second downlink physical signals, wherein the transmission indication information indicates indexes of transmitted second downlink physical signals in a third transmission periodicity, and/or indexes of non-transmitted second downlink physical signals; the third transmission periodicity, wherein at least one first downlink physical signal and at least one second downlink physical signal are transmitted in the third transmission periodicity; a periodicity of the third transmission periodicity; or a transmission pattern of the second downlink physical signals, wherein the transmission pattern indicates an index of a first symbol of candidate second downlink physical signals in a time unit.

In combination with one or more aspects of the method performed by the base station described above, for example, the configuration information further includes first configuration information related to a first random access and second configuration information related to a second random access, wherein the first configuration information is associated with the set of first downlink physical signals and the second configuration information is associated with the set of second downlink physical signals.

In combination with one or more aspects of the above-described method performed by a base station, for example, the second configuration information includes at least one of: a configuration index; a mapping ratio of downlink physical signals to ROs, the mapping ratio indicating a number of ROs to which each downlink physical signal is mapped, the downlink physical signals including first downlink physical signals and/or a second downlink physical signals; a period related to random access; a number of frequency multiplexed ROs; a frequency domain starting position of ROs; a root sequence index; a number of preambles; or a power-related configuration.

In combination with one or more aspects of the method performed by the base station described above, for example, all or part of the content of the second configuration information is the same as all or part of the content of the first configuration information.

In combination with one or more aspects of the method performed by the base station described above, for example, the second configuration information and the first configuration information are the same with respect to at least one of: a configuration index; a number of frequency multiplexed ROs; a frequency domain starting position of ROs; a root sequence index; a number of preambles; or a power-related configuration.

In combination with one or more aspects of the method performed by the base station described above, for example, he valid ROs includes first valid ROs associated with a first random access and/or second valid ROs associated with a second random access.

In combination with one or more aspects of the method performed by the base station described above, for example, the set of first downlink physical signals includes first downlink physical signals and the set of second downlink physical signals includes second downlink physical signals, and wherein an RO in a random access time unit is a valid RO in case that at least one of the following conditions is satisfied: the RO is within uplink symbols determined based on at least one of a first time division duplex (TDD) uplink and/or downlink configuration or a second TDD uplink and/or downlink configuration; the RO does not precede the first downlink physical signal and/or the second downlink physical signal in the random access time unit, and/or the RO is at least N1 symbols after a last downlink symbol in the random access time unit and/or a last symbol of the first downlink physical signal and/or the second downlink physical signal in the random access time unit; a first symbol of the RO is at least N2 symbols after a last symbol determined based on the second TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal; the first symbol of the RO is at least N3 symbols after the last downlink symbol determined based on the second TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal, and N4 symbols before the last downlink symbol determined based on the first TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal; the first symbol of the RO is at least N5 symbols after the last downlink symbol determined based on the second TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal, and N6 symbols before the last downlink symbol determined based on the first TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal; or the first symbol of the RO is at least N7 symbols after the last downlink symbol determined based on the second TDD uplink and/or downlink configuration and/or a last SSB symbol, and before N8 symbols after the last downlink symbol determined based on the first TDD uplink and/or downlink configuration and/or the last symbol of the first downlink physical signal and/or the second downlink physical signal.

In combination with one or more aspects of the method performed by the base station described above, for example, receiving the random access preamble based on one or more valid ROs includes: determining an available RO from the one or more valid ROs based on a mapping of first downlink physical signals and/or second downlink physical signals to ROs and a transmitted first downlink physical signal and/or a transmitted second downlink physical signal; and receiving the random access preamble in the available RO.

In combination with one or more aspects of the method performed by the base station described above, for example, the mapping of first downlink physical signals and/or second downlink physical signals to ROs includes one or more of the following: the first downlink physical signals are mapped to first valid ROs among first ROs associated with a first random access, and the second downlink physical signals are mapped to remaining ROs among the first ROs other than the first valid ROs, the second downlink physical signals are mapped to first valid ROs corresponding to a third index group, wherein the third index group is based on at least one of a first index group determined based on indication information of the first downlink physical signals transmitted in the first downlink physical signals or a second index group determined based on indication information of the second downlink physical signals transmitted in the second downlink physical signals; the second downlink physical signals are mapped only to second valid ROs, wherein the resources of the second valid ROs are different from that of the first valid ROs; in case that the resources of the second valid ROs partially overlaps with the resources of the first valid ROs, the second downlink physical signals are mapped only to ROs not overlapping with the first valid ROs among the second valid ROs; the second downlink physical signals are mapped to the remaining ROs other than the first valid ROs among the first ROs and the first valid ROs corresponding to the third index group; or the second downlink physical signals are mapped to the first valid ROs corresponding to the third index group and the second valid ROs.

In combination with one or more aspects of the method performed by the base station described above, for example, the third index group is determined based on the first configuration information and/or second indication information included in the configuration information, wherein the second indication information indicates indexes of first downlink physical signals in the set of first downlink physical signals.

In combination with one or more aspects of the method performed by the base station described above, for example, the method further includes transmitting feedback information for the random access preamble, comprising at least one of: transmitting the feedback information using a first radio network temporary identifier (RNTI), wherein the first RNTI includes at least one of: an RNTI determined based on ROs for receiving the random access preamble, a cell radio network temporary identifier (C-RNTI), or an RNTI configured for the UE for receiving the feedback information; or transmitting the feedback information in a control resource set (COREST) and/or search space, wherein the COREST and/or search space is specific to a UE supporting network energy saving, or specific to network energy saving random access, or specific to a UE sending the random access preamble for the RO of the second random access configuration.

According to some aspects of the disclosure, a UE in a wireless communication system is also provided. The UE includes: a transceiver; and one or more processors coupled with the transceiver and configured to perform one or more aspects of the above method performed by the UE.

According to some aspects of the disclosure, a base station in a wireless communication system is also provided. The base station includes: a transceiver; and one or more processors coupled with the transceiver and configured to perform one or more aspects of the above-described method performed by the base station.

According to some aspects of the disclosure, there is also provided a computer-readable storage medium having stored thereon one or more computer programs that, when executed by one or more processors, may implement one or more aspects of the above-described method performed by a UE.

According to some aspects of the disclosure, there is also provided a computer-readable storage medium having stored thereon one or more computer programs that, when executed by one or more processors, may implement one or more aspects of the above-described method performed by a base station.

The following FIGS. 1- 3B describe various embodiments implemented by using orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) communication technologies in wireless communication systems. The descriptions of FIGS. 1- 3B do not mean physical or architectural implications for the manner in which different embodiments may be implemented. Different embodiments of the disclosure may be implemented in any suitably arranged communication systems.

FIG. 1 illustrates an example wireless network 100 according to some embodiments of the disclosure. The embodiment of the wireless network 100 shown in FIG. 1 is for illustration only. Other embodiments of the wireless network 100 may be used without departing from the scope of the disclosure.

The wireless network 100 includes a gNodeB (gNB) 101, a gNB 102, and a gNB 103. gNB 101 communicates with gNB 102 and gNB 103. gNB 101 also communicates with at least one Internet Protocol (IP) network 130, such as the Internet, a private IP network, or other data networks.

Depending on a type of the network, other well-known terms such as “base station (BS)” or “access point” may be used instead of “gNodeB” or “gNB”. For convenience, the terms “gNodeB” and “next generation node B (gNB)” are used in this patent document to refer to network infrastructure components that provide wireless access for remote terminals. And, depending on the type of the network, other well-known terms such as “mobile station”, “user station”, “remote terminal”, “wireless terminal” or “user apparatus” may be used instead of “user equipment” or “UE”. For example, the terms “terminal”, “user equipment” and “UE” may be used in this patent document to refer to remote wireless devices that wirelessly access the gNB, no matter whether the UE is a mobile device (such as a mobile phone or a smart phone) or a fixed device (such as a desktop computer or a vending machine).

According to an embodiment, a gNB 102 provides wireless broadband access to the network 130 for a first plurality of UEs within a coverage area 120 of gNB 102. The first plurality of UEs include a UE 111, which may be located in a Small Business (SB); a UE 112, which may be located in an enterprise (E); a UE 113, which may be located in a WiFi Hotspot (HS); a UE 114, which may be located in a first residence (R); a UE 115, which may be located in a second residence (R); a UE 116, which may be a mobile device (M), such as a cellular phone, a wireless laptop computer, a wireless PDA, etc. GNB 103 provides wireless broadband access to network 130 for a second plurality of UEs within a coverage area 125 of gNB 103. The second plurality of UEs include a UE 115 and a UE 116. In some implementations, one or more of gNBs 101-103 may communicate with each other and with UEs 111-116 using 5G, Long Term Evolution (LTE), LTE-A, WiMAX or other advanced wireless communication technologies.

The dashed lines show approximate ranges of the coverage areas 120 and 125, and the ranges are shown as approximate circles merely for illustration and explanation purposes. It should be clearly understood that the coverage areas associated with the gNBs, such as the coverage areas 120 and 125, may have other shapes, including irregular shapes, depending on configurations of the gNBs and changes in the radio environment associated with natural obstacles and man-made obstacles.

As will be described in more detail below, one or more of gNB 101, gNB 102, and gNB 103 include a 2D antenna array as described in embodiments of the disclosure. In some implementations, one or more of gNB 101, gNB 102, and gNB 103 support codebook designs and structures for systems with 2D antenna arrays.

Although FIG. 1 illustrates an example of the wireless network 100, various changes may be made to FIG. 1. The wireless network 100 may include any number of gNBs and any number of UEs in any suitable arrangement, for example. Furthermore, gNB 101 may directly communicate with any number of UEs and provide wireless broadband access to the network 130 for those UEs. Similarly, each gNB 102-103 may directly communicate with the network 130 and provide direct wireless broadband access to the network 130 for the UEs. In addition, gNB 101, 102 and/or 103 may provide access to other or additional external networks, such as external telephone networks or other types of data networks.

FIGS. 2A and 2B illustrate example wireless transmission and reception paths according to some embodiments of the disclosure. In the following description, the transmission path 200 may be described as being implemented in a gNB, such as gNB 102, and the reception path 250 may be described as being implemented in a UE, such as UE 116. However, it should be understood that the reception path 250 may be implemented in a gNB and the transmission path 200 may be implemented in a UE. In some implementations, the reception path 250 is configured to support codebook designs and structures for systems with 2D antenna arrays as described in embodiments of the disclosure.

The transmission path 200 includes a channel coding and modulation block 205, a Serial-to-Parallel (S-to-P) block 210, a size N Inverse Fast Fourier Transform (IFFT) block 215, a Parallel-to-Serial (P-to-S) block 220, a cyclic prefix addition block 225, and an up-converter (UC) 230. The reception path 250 includes a down-converter (DC) 255, a cyclic prefix removal block 260, a Serial-to-Parallel (S-to-P) block 265, a size N Fast Fourier Transform (FFT) block 270, a Parallel-to-Serial (P-to-S) block 275, and a channel decoding and demodulation block 280.

In the transmission path 200, the channel coding and modulation block 205 receives a set of information bits, applies coding (such as Low Density Parity Check (LDPC) coding), and modulates the input bits (such as using Quadrature Phase Shift Keying (QPSK) or Quadrature Amplitude Modulation (QAM)) to generate a sequence of frequency domain modulated symbols. The Serial-to-Parallel (S-to-P) block 210 converts (such as demultiplexes) serial modulated symbols into parallel data to generate N parallel symbol streams, where N is a size of the IFFT/FFT used in gNB 102 and UE 116. The size N IFFT block 215 performs IFFT operations on the N parallel symbol streams to generate a time domain output signal. The Parallel-to-Serial block 220 converts (such as multiplexes) parallel time domain output symbols from the Size N IFFT block 215 to generate a serial time domain signal. The cyclic prefix addition block 225 inserts a cyclic prefix into the time domain signal. The up-converter 230 modulates (such as up-converts) the output of the cyclic prefix addition block 225 to an RF frequency for transmission via a wireless channel. The signal may also be filtered at a baseband before switching to the RF frequency.

According to an embodiment, the RF signal transmitted from gNB 102 arrives at UE 116 after passing through the wireless channel, and operations in reverse to those at gNB 102 are performed at UE 116. The down-converter 255 down-converts the received signal to a baseband frequency, and the cyclic prefix removal block 260 removes the cyclic prefix to generate a serial time domain baseband signal. The Serial-to-Parallel block 265 converts the time domain baseband signal into a parallel time domain signal. The Size N FFT block 270 performs an FFT algorithm to generate N parallel frequency domain signals. The Parallel-to-Serial block 275 converts the parallel frequency domain signal into a sequence of modulated data symbols. The channel decoding and demodulation block 280 demodulates and decodes the modulated symbols to recover the original input data stream.

Each of gNBs 101-103 may implement a transmission path 200 similar to that for transmitting to UEs 111-116 in the downlink, and may implement a reception path 250 similar to that for receiving from UEs 111-116 in the uplink. Similarly, each of UEs 111-116 may implement a transmission path 200 for transmitting to gNBs 101-103 in the uplink, and may implement a reception path 250 for receiving from gNBs 101-103 in the downlink.

Each of the components in FIGS. 2A and 2B may be implemented using only hardware, or using a combination of hardware and software/firmware. As a specific example, at least some of the components in FIGS. 2A and 2B may be implemented in software, while other components may be implemented in configurable hardware or a combination of software and configurable hardware. For example, the FFT block 270 and IFFT block 215 may be implemented as configurable software algorithms, in which the value of the size N may be modified according to the implementation.

Furthermore, although described as using FFT and IFFT, this is only illustrative and should not be interpreted as limiting the scope of the disclosure. Other types of transforms may be used, such as Discrete Fourier transform (DFT) and Inverse Discrete Fourier Transform (IDFT) functions. It should be understood that for DFT and IDFT functions, the value of variable N may be any integer (such as 1, 2, 3, 4, etc.), while for FFT and IFFT functions, the value of variable N may be any integer which is a power of 2 (such as 1, 2, 4, 8, 16, etc.).

Although FIGS. 2A and 2B illustrate examples of wireless transmission and reception paths, various changes may be made to FIGS. 2A and 2B. For example, various components in FIGS. 2A and 2B may be combined, further subdivided or omitted, and additional components may be added according to specific requirements. Furthermore, FIGS. 2A and 2B are intended to illustrate examples of types of transmission and reception paths that may be used in a wireless network. Any other suitable architecture may be used to support wireless communication in a wireless network.

FIG. 3A illustrates an example UE 116 according to the present disclosure. The embodiment of UE 116 shown in FIG. 3A is for illustration only, and UEs 111-115 of FIG. 1 may have the same or similar configuration. However, a UE has various configurations, and FIG. 3A does not limit the scope of the present disclosure to any specific implementation of the UE.

UE 116 includes an antenna 301, a radio frequency (RF) transceiver 302, a transmission (TX) processing circuit 303, a microphone 304, and a reception (RX) processing circuit 305. UE 116 also includes a speaker 306, a controller/processor 307, an input/output (I/O) interface 308, an input device(s) 309, a display 310, and a memory 311. The memory 311 includes an operating system (OS) 312 and one or more applications 313.

The RF transceiver 302 receives an incoming RF signal transmitted by a gNB of the wireless network 100 from the antenna 301. The RF transceiver 302 down-converts the incoming RF signal to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is transmitted to the RX processing circuit 305, where the RX processing circuit 305 generates a processed baseband signal by filtering, decoding and/or digitizing the baseband or IF signal. The RX processing circuit 305 transmits the processed baseband signal to speaker 306 (such as for voice data) or to controller/processor 307 for further processing (such as for web browsing data).

The TX processing circuit 303 receives analog or digital voice data from microphone 304 or other outgoing baseband data (such as network data, email or interactive video game data) from controller/processor 307. The TX processing circuit 303 encodes, multiplexes, and/or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 302 receives the outgoing processed baseband or IF signal from the TX processing circuit 303 and up-converts the baseband or IF signal into an RF signal transmitted via the antenna 301.

The controller/processor 307 can include one or more processors or other processing devices and execute an OS 312 stored in the memory 311 in order to control the overall operation of UE 116. For example, the controller/processor 307 can control the reception of forward channel signals and the transmission of backward channel signals through the RF transceiver 302, the RX processing circuit 305 and the TX processing circuit 303 according to well-known principles. In some embodiments, the controller/processor 307 includes at least one microprocessor or microcontroller.

The controller/processor 307 is also capable of executing other processes and programs residing in the memory 311, such as operations for channel quality measurement and reporting for systems with 2D antenna arrays as described in embodiments of the present disclosure. The controller/processor 307 can move data into or out of the memory 311 as required by an execution process. In some embodiments, the controller/processor 307 is configured to execute the application 313 based on the OS 312 or in response to signals received from the gNB or the operator. The controller/processor 307 is also coupled to an I/O interface 308, where the I/O interface 308 provides UE 116 with the ability to connect to other devices such as laptop computers and handheld computers. I/O interface 308 is a communication path between the accessories and the controller/processor 307.

The controller/processor 307 is also coupled to the input device(s) 309 and the display 310. An operator of UE 116 can input data into UE 116 using the input device(s) 309. The display 310 may be a liquid crystal display or other display capable of presenting text and/or at least limited graphics (such as from a website). The memory 311 is coupled to the controller/processor 307. A part of the memory 311 can include a random access memory (RAM), while another part of the memory 311 can include a flash memory or other read-only memory (ROM).

Although FIG. 3A illustrates an example of UE 116, various changes can be made to FIG. 3A. For example, various components in FIG. 3A can be combined, further subdivided or omitted, and additional components can be added according to specific requirements. As a specific example, the controller/processor 307 can be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). Furthermore, although FIG. 3A illustrates that the UE 116 is configured as a mobile phone or a smart phone, UEs can be configured to operate as other types of mobile or fixed devices.

According to an embodiment, two or more UEs 116 may communicate directly using one or more sidelink channels (for example, without using a base station as a medium for communication with each other). For example, the UE 116 may communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocol (which, for example, may include vehicle-to-vehicle (V2V) protocol, vehicle-to-infrastructure (V2I) protocol, etc.), mesh network, etc. In this case, the UE 116 may perform scheduling operations, resource selection operations, and/or other operations performed by the base station as described elsewhere herein. For example, the base station may configure the UE 116 via downlink control information (DCI), radio resource control (RRC) signaling, medium access control-control element (MAC-CE) or via system information (e.g., system information block (SIB)).

FIG. 3B illustrates an example gNB 102 according to some embodiments of the disclosure. The embodiment of gNB 102 shown in FIG. 3B is for illustration only, and other gNBs of FIG. 1 can have the same or similar configuration. However, a gNB has various configurations, and FIG. 3B does not limit the scope of the disclosure to any specific implementation of a gNB. It should be noted that gNB 101 and gNB 103 can include the same or similar structures as gNB 102.

As shown in FIG. 3B, gNB 102 includes multiple antennas 370a-370n, multiple RF transceivers 372a-372n, a transmission (TX) processing circuit 374, and a reception (RX) processing circuit 376. In certain embodiments, one or more of the plurality of antennas 370a-370n include a 2D antenna array. gNB 102 also includes a controller/processor 378, a memory 380, and a backhaul or network interface 382.

RF transceivers 372a-372n receive an incoming RF signal from antennas 370a-370n, such as a signal transmitted by UEs or other gNBs. RF transceivers 372a-372n down-convert the incoming RF signal to generate an IF or baseband signal. The IF or baseband signal is transmitted to the RX processing circuit 376, where the RX processing circuit 376 generates a processed baseband signal by filtering, decoding and/or digitizing the baseband or IF signal. RX processing circuit 376 transmits the processed baseband signal to controller/processor 378 for further processing.

The TX processing circuit 374 receives analog or digital data (such as voice data, network data, email or interactive video game data) from the controller/processor 378. TX processing circuit 374 encodes, multiplexes and/or digitizes outgoing baseband data to generate a processed baseband or IF signal. RF transceivers 372a-372n receive the outgoing processed baseband or IF signal from TX processing circuit 374 and up-convert the baseband or IF signal into an RF signal transmitted via antennas 370a-370n.

The controller/processor 378 can include one or more processors or other processing devices that control the overall operation of gNB 102. For example, the controller/processor 378 can control the reception of forward channel signals and the transmission of backward channel signals through the RF transceivers 372a-372n, the RX processing circuit 376 and the TX processing circuit 374 according to well-known principles. The controller/processor 378 can also support additional functions, such as higher-level wireless communication functions. For example, the controller/processor 378 can perform a Blind Interference Sensing (BIS) process such as that performed through a BIS algorithm, and decode a received signal from which an interference signal is subtracted. A controller/processor 378 may support any of a variety of other functions in gNB 102. In some implementations, the controller/processor 378 includes at least one microprocessor or microcontroller.

The controller/processor 378 is also capable of executing programs and other processes residing in the memory 380, such as a basic OS. The controller/processor 378 can also support channel quality measurement and reporting for systems with 2D antenna arrays as described in embodiments of the disclosure. In some implementations, the controller/processor 378 supports communication between entities such as web RTCs. The controller/processor 378 can move data into or out of the memory 380 as required by an execution process.

The controller/processor 378 is also coupled to the backhaul or network interface 382. The backhaul or network interface 382 allows gNB 102 to communicate with other devices or systems through a backhaul connection or through a network. The backhaul or network interface 382 can support communication over any suitable wired or wireless connection(s). For example, when gNB 102 is implemented as a part of a cellular communication system, such as a cellular communication system supporting 5G or new radio access technology or NR, LTE or LTE-A, the backhaul or network interface 382 can allow gNB 102 to communicate with other gNBs through wired or wireless backhaul connections. When gNB 102 is implemented as an access point, the backhaul or network interface 382 can allow gNB 102 to communicate with a larger network, such as the Internet, through a wired or wireless local area network or through a wired or wireless connection. The backhaul or network interface 382 includes any suitable structure that supports communication through a wired or wireless connection, such as an Ethernet or an RF transceiver.

The memory 380 is coupled to the controller/processor 378. A part of the memory 380 can include an RAM, while another part of the memory 380 can include a flash memory or other ROMs. In certain embodiments, multiple instructions, such as the BIS algorithm, are stored in the memory. The plurality of instructions are configured to cause the controller/processor 378 to execute the BIS process and decode the received signal after subtracting at least one interference signal determined by the BIS algorithm.

As will be described in more detail below, the transmission and reception paths of gNB 102 (implemented using RF transceivers 372a-372n, TX processing circuit 374 and/or RX processing circuit 376) support aggregated communication with FDD cells and TDD cells.

Although FIG. 3B illustrates an example of gNB 102, various changes may be made to FIG. 3B. For example, gNB 102 can include any number of each component shown in FIG. 3A. As a specific example, the access point can include many backhaul or network interfaces 382, and the controller/processor 378 can support routing functions to route data between different network addresses. As another specific example, although shown as including a single instance of the TX processing circuit 374 and a single instance of the RX processing circuit 376, gNB 102 can include multiple instances of each (such as one for each RF transceiver).

Those skilled in the art will understand that, "terminal" and "terminal device" as used herein include not only devices with wireless signal receiver which have no transmitting capability, but also devices with receiving and transmitting hardware which can carry out bidirectional communication on a bidirectional communication link. Such devices may include cellular or other communication devices with single-line displays or multi-line displays or cellular or other communication devices without multi-line displays; a PCS (personal communications service), which may combine voice, data processing, fax and/or data communication capabilities; a PDA (Personal Digital Assistant), which may include a radio frequency receiver, a pager, an internet/intranet access, a web browser, a notepad, a calendar and/or a GPS (Global Positioning System) receiver; a conventional laptop and/or palmtop computer or other devices having and/or including a radio frequency receiver. "Terminal" and "terminal device" as used herein may be portable, transportable, installed in vehicles (aviation, sea transportation and/or land), or suitable and/or configured to operate locally, and/or in distributed form, operate on the earth and/or any other position in space. "Terminal" and "terminal device" as used herein may also be a communication terminal, an internet terminal, a music/video playing terminal, such as a PDA, a MID (Mobile Internet Device) and/or a mobile phone with music/video playing functions, a smart TV, a set-top box and other devices.

In describing a wireless communication system and in the disclosure described below, transferring methods (or configuration methods) of higher layer signaling or higher layer signals may be signal transferring methods for transferring information from a base station to a terminal over a downlink data channel of a physical layer or from a terminal to a base station over an uplink data channel of a physical layer, and examples of the signal transferring methods may include signal transferring methods for transferring information via Radio Resource Control (RRC) signaling, Packet Data Convergence Protocol (PDCP) signaling, or a Medium Access Control (MAC) Control Element (CE).

In the following description of the example embodiments of the disclosure, higher layer signaling may be signaling corresponding to at least one or a combination of one or more of the following signaling.

- MIB (master information block)

- SIB (system information block) or SIB X (X = 1,2, ...)

- RRC signaling

- MAC CE

Physical layer (Layer 1 (L1)) signaling may be signaling corresponding to at least one or a combination of one or more of the following signaling.

- PDCCH (physical downlink control channel)

- DCI (downlink control information)

- UE-specific DCI

- group common DCI

- common DCI (e.g., multicast DCI)

- scheduling DCI (for example, DCI for scheduling downlink or uplink data)

- non-scheduling DCI (for example, DCI other than DCI for scheduling downlink or uplink data)

- PUCCH (physical uplink control channel)

- UCI (uplink control information)

- Paging

- PRACH (physical random access channel)

- RAR (random access response)

According to an embodiment, uplink control signaling may include physical layer signaling and/or higher layer signaling. As described above, the physical layer signaling may include UCI and/or PUCCH and/or PRACH, and the higher layer signaling may include RRC signaling and/or MAC CE.

According to an embodiment, downlink control signaling may include physical layer signaling and/or higher layer signaling. As mentioned above, the physical layer signaling may include one or more of PDCCH, DCI, UE-specific DCI, group common DCI, common DCI, scheduling DCI (for example, DCI for scheduling downlink or uplink data), non-scheduling DCI, paging, and RAR, and the higher layer signaling may include one or more of a MIB, a SIB or SIB X (X = 1, 2, ...), RRC signaling or a MAC CE. Therefore, "configuring or indicating Y through downlink control signaling" will be understood as configuring or indicating Y through physical layer signaling, or configuring or indicating Y through higher layer signaling, or configuring or indicating Y through a combination of higher layer signaling and physical layer signaling.

According to an embodiment, a time domain unit (also referred to as a time unit) may be: a OFDM symbol, a OFDM symbol group (consisting of multiple OFDM symbols), a slot, one slot group (consisting of multiple slots), a subframe, ae subframe group (consisting of multiple subframes), a system frame, and/or a system frame group (consisting of multiple system frames). A time domain unit also be an absolute time unit, such as 1 millisecond, 1 second, etc. A time unit may also be a combination of multiple granularities, e.g., P1 slots plus P2 OFDM symbols, P1 and/or P2 may be positive integers.

According to an embodiment, a frequency domain unit (also referred to as a frequency unit) may be: a subcarrier, a subcarrier group (consisting of multiple subcarriers), a resource block (RB), which may also be referred to as a physical resource block (PRB), a resource block group (consisting of multiple RBs), a bandwidth part (BWP), a BWP group (consisting of multiple BWPs), a band/carrier, and/or a band group/carrier group. The frequency domain unit may also be an absolute frequency domain unit, such as 1 Hz, 1 kHz, or the like. The frequency domain unit may also be a combination of multiple granularities, e.g., M1 PRBs plus M2 subcarriers, where M1 and/or M2 may be positive integers.

According to an embodiment, the term "transmit" may be interchangeably used with "send", "report", "notify", or the like.

The transmission links of a wireless communication system primarily include downlink communication links from a network (e.g., a base station, such as 5G gNB) to a UE, and uplink communication links from the UE to the network.

A node for positioning measurements in a wireless communication system (e.g., current wireless communication systems) may include at least one of a UE that initiates a positioning request message, a Location Management Function (LMF) for UE positioning and positioning assistance data transmission, a gNB or transmission reception point (TRP) for sending broadcast positioning assistance data and for uplink positioning measurement, or a UE for downlink positioning measurement. Furthermore, the method according to example embodiments of the disclosure may also be extended to be applied in other communication systems, such as vehicle-to-everything (V2X) communication, e.g., sidelink communication, and in this case, the transmission reception point or UE may be any one of the devices in V2X.

Transmissions in a wireless communication system may include: transmissions (referred to as downlink transmissions) from a base station (e.g., gNB) to a UE, where a corresponding time unit (e.g., slot) may be referred to as a downlink time unit (e.g., downlink slot); transmissions (referred to as uplink transmissions) from a UE to a base station device, where the corresponding time unit (e.g., slot) may be referred to as an uplink time unit (e.g., uplink slot).

In a wireless communication system, such as an LTE or NR system, a random access procedure (e.g., a 2-step or 4-step random access procedure) may be employed to establish a link between a UE and a base station. The base station may periodically transmit a synchronization signal and a broadcast channel to a user (e.g., UE) through synchronization signal blocks (synchronization signal/physical broadcast channel (PBCH) blocks (SSBs), or referred to as first downlink physical signals). The period for transmitting the SSBs may be referred to as a synchronization signal block periodicity (SSB periodicity), or as a synchronization signal block burst period (SSB burst periodicity). In this case, the base station may configure a random access configuration period (e.g., physical random access channel (PRACH) configuration period). Within the period (e.g., PRACH configuration period), a certain number of physical random access channel occasions (PRACH occasions), which may also be referred to as random access channel occasions (RACH occasions, ROs), may be configured. Valid ROs of the configured ROs may be determined. For example, valid ROs may be determined from the configured ROs based on a certain method for determining the validity of the ROs (referred to as a validity determination method or validity rule). For example, it may be satisfied that all SSBs within an association or mapping period (e.g., a certain time period or time length) can be mapped to corresponding valid ROs. All SSBs within an SSB period can be exactly mapped to the required random access resources in an SSB-RO mapping cycle. There may be one or more mapping cycles in an association period. An SSB-RO mapping or association pattern period may include one or more association periods, and the SSB-RO mapping pattern in each association pattern period is the same.

Examples of the validity determination method or validity rule are as follows. An RO in a random access slot (PRACH slot) is valid in case that it is within an uplink symbol (or uplink part) in a TDD configuration pattern (e.g., TDD-UL-DL-ConfigurationCommon and/or tdd-UL-DL-ConfigurationDedicated). An RO in a random access slot is valid in case that the RO does not precede a SSB in the slot and/or the RO starts at least N (N may be a configured value or a predetermined value) symbols after a last downlink symbol and/or at least N symbols after a last SSB symbol in the current slot. Any suitable validity determination method or validity rule may be provided.

In new radio (NR) communication systems, the performance of random access directly affects a user's experience when radio resource control is established, e.g., during a random access procedure. In conventional wireless communication systems such as LTE and LTE-Advanced, or in 5G or NR systems, a random access procedure is applied to multiple scenarios such as initial connection setup, cell handover, uplink re-establishment, RRC connection re-establishment, etc., and divided into contention-based random access and contention-free random access according to whether a user (e.g., UE) is exclusive to a preamble resource. Since each user (e.g., UE) selects a preamble sequence from the same preamble sequence resource in attempting to establish an uplink in contention-based random access, it may occur that multiple users (e.g., UEs) select a same preamble sequence to transmit to the base station. Therefore, the contention resolution mechanism is an important direction of study in random access, and how to reduce contention probability, how to quickly resolve contention that have occurred, are key indicators affecting random access performance.

FIG. 3C illustrates a schematic diagram of a 4-step random access procedure according to some example embodiments of the disclosure. For example, the contention-based random access procedure is divided into four steps, as shown in FIG. 3C. In step 1, a UE randomly selects a preamble sequence (also referred to herein interchangeably as "preamble") from a resource pool of preamble sequences to send to a base station. The base station performs correlation detection on the received signal, thereby identifying the preamble sequence sent by the UE. In step 2, the base station sends a random access response (RAR) to the UE. The RAR may include a random access preamble sequence identifier, a timing advance indication determined from a delay estimate between the UE and the base station, a temporary cell-radio network temporary identifier (C-RNTI), and/or time-frequency resources allocated for the next uplink transmission of the UE (a time-frequency resource may refer to a time domain resource and/or a frequency domain resource). The UE may search for a PDCCH carrying the feedback based on the RA-RNTI associated with the PRACH occasion in which the random access preamble sequence is transmitted. The RA-RNTI associated with the PRACH occasion (e.g., RO) in which the random access preamble sequence is transmitted may be based on the index of the first OFDM symbol of the PRACH occasion, the index of the first slot of the PRACH occasion in the system frame, the index of the PRACH occasion in the frequency domain, the UL carrier used for the random access preamble transmission. For example, the RA-RNTI may be calculated as follows:

RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id,

where s_id is the index of the first OFDM symbol of the PRACH occasion (0 ≤ s_id < 14); t_id is the index of the first slot of the PRACH occasion in the system frame (0 < t_id < 80), where the subcarrier spacing used to determine t_id is based on the value of μ for μ = {0, 1, 2, 3}, and t_id is the index of the slot for 120 kHz including the PRACH occasion in the system frame (0 < t_id < 80) for μ = {5, 6}; f_id is the index of the PRACH occasion in the frequency domain (0 < f_id < 8); ul_carrier_id is the UL carrier used for random access preamble transmission (0 for NUL carrier, and 1 for SUL carrier).

In step 3, the UE sends a message 3 (Msg3) to the base station according to the information in the RAR. The Msg3 includes information such as a UE identity (which is unique to the UE) and an RRC connection request, for resolving the conflict. In step 4, the base station sends a contention resolution identity to the UE, including the identity of the UE that succeeds in the contention resolution. The UE, after detecting its own identity, upgrades the temporary C-RNTI to C-RNTI and sends an acknowledgement (ACK) signal to the base station, completes the random access procedure, and waits for scheduling by the base station. Otherwise, the UE will start a new random access procedure after a delay.

For the contention-free random access procedure, the UE may be assigned a preamble sequence due to the base station knows the UE identity of the UE. Therefore, the UE does not need to randomly select a sequence when transmitting the preamble sequence, but uses the allocated preamble sequence. After detecting the allocated preamble sequence, the base station transmits a corresponding random access response including a timing advance and uplink resource allocation information. After receiving the random access response, the UE considers that uplink synchronization has been completed and waits for further scheduling by the base station. Therefore, the contention-free random access procedure includes only two steps: step 1, transmission of a preamble sequence, and step 2, transmission of a random access response.

For example, the random access procedure may be applicable to the following scenarios:

- initial access from RRC_IDLE;

- RRC connection re-establishment;

- cell handover;

- downlink data arrival during RRC connected state requiring random access procedure (when uplink is unsynchronized);

- uplink data arrival during RRC connected state requiring random access procedure (when uplink is unsynchronized or no resource is allocated for scheduling request in PUCCH resources);

- positioning.

Valid ROs may be determined from the configured ROs (e.g., based on determining the RO validity determination method). It is satisfied that all SSBs within an association period (a certain time period or time length) can be mapped to the corresponding valid ROs. All SSBs within an SSB period can be exactly mapped to the required random access resources within an SSB-RO mapping cycle. There may be one or more mapping cycles within an association period. An SSB-RO association pattern period includes one or more association periods, and the SSB-RO association pattern in each association pattern period is the same.

The base station may configure a random access configuration period (e.g., PRACH configuration period) within which a certain number of ROs are configured. Valid ROs are determined from the configured ROs by using a certain validity determination method or validity rule. It is satisfied that all SSBs within an association period (a certain time length) can be mapped to the corresponding valid ROs, all SSBs within an SSB period can be exactly mapped to the required random access resources within an SSB-RO mapping cycle. There may be one or more mapping cycles in an association period. An SSB-RO association pattern period includes one or more association periods, and the SSB-RO mapping pattern in each association pattern period is the same.

Note that ROs configured for each SSB by the base station is uniform; that is, when multiple SSBs exist, the number of ROs corresponding to each SSB is the same. When the distribution of UEs in a cell is uniform, the probability of a UE performing random access based on SSBs corresponding to beams to different directions is the same or similar. But in practice the distribution of UEs in a cell is not uniform due to the limitation of the geographical environment, so the probability of a UE selecting different beams for random access is not the same. For example, most UEs may transmit a preamble sequence for random access in valid ROs associated with some SSBs; e.g., the density of UEs in the beam direction of some SSBs may be greater than that in the beam direction of other SSBs. Optionally, in valid ROs associated with certain SSBs, fewer or no UEs may send a preamble sequence for random access. Different probabilities of UE random access in different ROs may result in a reduced probability of efficient random access detection by the base station, which is not conducive to energy savings in the network. In an example embodiment of the disclosure, efficient random access detection refers to that the base station is able to detect a UE performing random access.

There is a need to solve the problem of low effective random access detection probability by a base station due to non-uniform distribution of UEs within a cell. According to the solutions proposed by the example embodiments of the disclosure, non-uniform RO resource configuration of different SSB can be achieved, overall random access resource configuration is optimized, which can help the base station to improve efficient random access detection, thereby saving network energy consumption.

According to example embodiments of the disclosure, a method of spatially adaptive random access channel resource configuration is provided. The method can achieve the configuration of non-uniform random access resources by configuring multiple beam sweeping patterns, and the association manner of the corresponding random access resources. The method is applicable to scenarios of random access of UEs non-uniformly distributed in a cell, and appropriately configures random access resources, such as ROs or preambles, for SSBs of different beams, so that UEs densely distributed in certain beam directions can get more chances of random access, and thus the probability of collisions is reduced. Moreover, the method may also reduce the random access detection of the base station in the random access resources by reducing the configuration of random resources in certain beam directions, thereby saving network energy.

For example, random access resources may be configured for other features (e.g., network energy saving (NES)). It needs to be considered to perform random access in case that random access resources are configured for other features (e.g., NES). Example embodiments according to the disclosure propose a method for random access in a system in which random access resources are configured for other features (e.g., NES), such as random access configuration, random access resource determination, SSB-RO mapping, and/or the like.

It should be noted that the problems that can be solved by the disclosure are not limited to those mentioned above and in the following description, but can also solve all the problems that can be actually solved according to the essence of the technology of the disclosure.

For convenience of description, random accesses associated with a specific feature (e.g., NES) (e.g., random access resources may be used for random access as well as the specific feature) may be referred to as "second-type random access" (or simply, "second random access"), resources configured for the second random access may be referred to as "second-type random access resources" (or simply, "second random access resources") (e.g., second-type RO, or simply, second RO), and so on. The conventional random access may be referred to as "normal random access" or "first-type random access" (or simply, "first random access"), and the resources corresponding to the first random access may be referred to as "normal random access resources" (e.g., normal ROs) or "first-type random access resources" (or simply, "first random access resources") (e.g., first-type ROs, or simply first ROs).

It should be noted that the example embodiments of the disclosure have described the SSB as the downlink physical signal related to random access, but this is merely exemplary, and the SSB may be replaced by other downlink physical signals, such as downlink reference signals, e.g., channel state information reference signals (CSI-RS), positioning reference signals (PRS), and/or the like.

According to an embodiment, the configuration information includes at least one of information configured by a base station, information indicated in a received signaling, information configured a higher layer, preconfigured information, if not otherwise specified. Further, it may be a set of configuration information obtained by the above method; there may also be multiple sets of configuration information obtained by the above method, from which the UE or node may select a set of configuration information to use according to a predefined condition; it may also be a set of configuration information obtained by the above method, and the set of configuration information includes multiple subsets from which the UE or node may select a subset for use according to a predefined condition.

FIG. 4 illustrates a flowchart of a method performed by a UE in a wireless communication system according to an example embodiment of the disclosure. Referring to FIG. 4, the method may include operations S410, S420, S430 and S440. It should be understood that at least one of the above-described operations may be omitted, or, alternatively, additional operations may be included, for example, one or more operations in the methods described in various embodiments according to the disclosure.

In operation S410, the UE acquires configuration information and/or command information. For example, the UE may receive the configuration information and/or command information transmitted by a base station.

According to an embodiment, the configuration information may include first information related to a set of first downlink physical signals (e.g., first-type SSB burst) (e.g., configuration information related to a set of first downlink physical signals (e.g., first-type SSB burst)) and second information related to a set of second downlink physical signals (e.g., second-type SSB burst) (e.g., configuration information related to a set of second downlink physical signals (e.g., second-type SSB burst)). The UE may determine valid RO(s) based on the first information and the second information (e.g., the methods described based on various embodiments of the disclosure). The UE may transmit a random access preamble on the determined valid RO. In this way, the determined valid RO does not affect the reception of the first or second downlink physical signals by the UE (e.g., the determined valid RO does not occupy time-frequency domain resources of the first and second downlink physical signals). Moreover, when the UE transmits a preamble on the determined valid RO for random access, there is no impact on the UE for random access based on only the valid RO determined by the first information.

For example, the first information is associated with a set of first downlink physical signals (e.g., first-type SSBs) and the second information is associated with a second set of physical signals (e.g., second-type SSBs).

According to an embodiment, the first information is for first-type UEs and the second information is for second-type UEs. For example, the first-type UEs may be UEs that do not support the NES feature, or the first-type UEs may be UEs of a first version (e.g., Release 17), the second-type UEs may be UEs that support the NES feature, or the second-type UEs may be UEs of a second version (e.g., Release 19).

According to an embodiment, the first information may include at least one of configuration and/or indication information related to the transmitted SSBs or related to the transmitted SSBs in a first-type SSB burst (which may also be referred to as first-type SSB set; in embodiments of the disclosure, also referred to as a set of first downlink physical signals, where the set of first downlink physical signals includes one or more first downlink physical signals). For example, the configuration or indication information may include at least one of: first indication information indicating the time domain positions (e.g., indexes) of the transmitted SSBs in a first-type SSB burst (e.g., higher layer parameter ssb-PositionsInBurst); the transmission periodicity of SSB and/or SSB burst (e.g., higher layer parameter ssb-periodicityServingCell);

According to an embodiment, the first information may further include configuration information related to first random access (first random access configuration information), where the configuration information may include at least one of: a random access configuration (e.g., PRACH configuration) index (e.g., higher layer parameter prach-ConfigurationIndex; according to the configuration, the following may be determined, a random access preamble format, a random access configuration period (first random access period), a number and positions of random access frames in the random access configuration period; indexes of subframes or slots in a random access frame, the starting symbol position of a random access preamble in a subframe or slot, the number of random access slots in a random access subframe, the number of ROs in a random access slot, the number of OFDM symbols occupied in an RO); a SSB-RO mapping cycle (first mapping cycle); an association period (first association period) for SSB-RO; an association pattern period for SSB-RO (first association pattern period); a configuration related to the number of ROs in frequency domain among first-type random access resources (e.g., higher layer parameter msg1-FDM); the frequency domain starting position of the frequency domain RO of the first-type random access resource (e.g., higher layer parameter msg1-FrequencyStart); the root sequence index of the preamble; the number of corresponding preambles in an RO; a mapping ratio (first ratio information) between SSBs and ROs (SSB-RO) (e.g., information indicating how many SSBs are mapped to one RO, e.g., higher layer parameter ssb-perRO); or a TDD configuration pattern (referred to as a first TDD pattern).

According to an embodiment, the ROs determined from the first random access configuration information are expressed as normal ROs or first-type ROs; specifically, valid normal ROs may be obtained from the configured normal ROs according to a predetermined validity rule (e.g., an existing validity rule), expressed as valid normal ROs. For example, the predetermined validity rule (e.g., existing validity rule) may include: an RO in a random access slot (PRACH slot) is valid in case that the RO is within an uplink symbol (or uplink portion) in the TDD configuration pattern; an RO in a random access slot is valid in case that the RO does not precede a SSB in the slot and/or the RO starts at least N symbols after a last downlink symbol and/or last SSB symbol in the current slot. In addition, the mapping between the first-type SSBs and the valid ROs may be a predetermined mapping rule or mapping order (e.g., an existing mapping rule or mapping order). For example, the predetermined mapping rule or mapping order (e.g., the existing mapping rule or mapping order) may include that the SSB indexes are mapped to the valid ROs in the following order: first, in ascending order of preamble indexes in a random access slot; second, in ascending order of frequency multiplexed ROs in frequency domain; third, in ascending order of time multiplexed ROs in time domain within the random access slot; fourth, in the next random access slot.

Note that the first random access configuration information may be referred to as configuration information related to normal random access or configuration information for the first random access, e.g., existing or existing random access configuration information, such as configuration information for four-step random access, random access configuration information for two-step, etc. The configuration for four-step random access is taken as an example in the example embodiments of the disclosure to describe the method. However, the embodiments of the disclosure are not limited thereto, and may be extended or replaced with random access configurations for other features. In addition, for convenience of description, the SSB burst configured in the first random access configuration information may be referred to as first-type SSB burst, where the first-type SSB burst may include one or more SSBs (in an example embodiment of the disclosure, an SSB in the first-type SSB burst may be referred to as a first-type SSB).

For example, the second information includes at least one of: configuration information related to a set of second downlink physical signals (e.g., second-type SSB burst), a TDD configuration pattern (or referred to as a second TDD pattern).

Here, the configuration information related to a set of second downlink physical signals (e.g., second-type SSB burst) includes at least one of: second indication information indicating indexes of one or more SSBs; configuration information related to time domain resources for second-type SSB burst; configuration information related to frequency domain resources for second-type SSB burst. Examples of respective configuration information are described separately below.

Second Indication Information

The second indication information may indicate indexes of one or more SSBs. For example, the second indication information may indicate indexes of the transmitted SSBs (e.g., the actually transmitted SSBs, alternatively, not actually transmitted SSBs) in a first-type SSB burst. Thus, the one or more SSBs indicated by the second indication information may include the indexes of the transmitted (e.g., actually transmitted) SSBs in a first-type SSB burst. The transmitted SSBs in a first-type SSB burst indicated by the second indication information may be the actually transmitted SSBs among the transmitted SSBs indicated by the first indication information.

In some implementation, the indexes (first index group) of the single or multiple transmitted SSBs in a first-type SSB burst may be obtained from the first indication information; a subset of indexes in the first index group may be determined based on the second indication information, where the ROs associated with the SSB indexes in the subset of indexes may be used for mapping (or association) of the SSBs in a second-type SSB burst.

In a method, a third index group may be determined from the first indication information and the second indication information, where the first indication information may indicate indexes (first index group) of the single or multiple transmitted SSBs in a first-type SSB burst, and the second indication information may indicate a single or multiple indexes (third index group) in the first index group, where the second index group may be a subset of the first index group.

Optionally, the second indication information may indicate a group of new indexes (second index group) of the single or multiple transmitted SSBs in a first-type SSB burst, where the second index group is a subset of the first index group, and the third index group may be determined according to the first index group and the second index group, e.g., the indexes in the third index group are included in the first index group but not included in the second index group; optionally, the indexes in the third index group are included in the second index group but not included in the first index group.

Specifically, the second indication information may indicate the time domain positions (e.g., indexes) of the transmitted (e.g., actually transmitted by the base station) SSBs in a first-type SSB burst. For example, the second indication information may indicate at least one transmitted SSB (e.g., at least one actual transmitted SSB) among the transmitted SSBs indicated by the first indication information. The UE may determine information about the transmitted SSBs in a first-type SSB burst according to the second indication information. For example, the UE may determine the indexes of the actually transmitted SSBs in a first-type SSB burst according to the second indication information. Optionally, the second indication information is different from the first indication information, and the UE may determine the indexes of the actually transmitted SSBs in a first-type SSB burst according to the first indication information and the second indication information. A specific example is described below. As an example, the UE may determine the indexes of the transmitted SSBs in a first-type SSB burst according to the first indication information; e.g., the UE receives the first indication information (e.g., inOneGroup, 8 bit bitmap), and identifies (or, knows) that the indexes of the transmitted SSBs in a first-type SSB burst is {0, 1, 2, 3, 4, 5, 6, 7}, referred to as the first index group, where the UE assumes that the leftmost 4 bits of the indication information (inOneGroup, 8 bit bitmap) are valid in case that the maximum number of SSBs per half frame is equal to 4, and the UE ignores the rightmost 4 bits; in case that the maximum number of SSB per half frame is equal to 8, all 8 bits of the indication information are valid. Specifically, the first/leftmost bit of the first indication information corresponds to SSB index 0, the second bit corresponds to SSB index 1, and so on. In case that the maximum number of SSBs per half frame is equal to 64, all 8 bits are valid; the first/leftmost bit corresponds to the first SSB indexes in the group (i.e., to SSB indexes 0, 8, etc.); the second bit corresponds to the second SSB block indexes in the group (i.e., to SSB indexes 1, 9, etc.), and so on. A value of 0 in the bitmap represents that the corresponding SSB is not transmitted, and a value of 1 represents that the corresponding SSB is transmitted. In case that the maximum number of SSBs per half frame is equal to 64, the UE may determine the indexes of the transmitted SSBs according to the first indication information and other indication information (e.g. groupPresence, 8 bit bitmap), where the first/leftmost bit of the indication information corresponds to SSB indexes 0-7, the second bit corresponds to SSB indexes 8-15, and so on. A value of 0 in the indication information indicates that there is no SSB according to inOneGroup. A value of 1 indicates that the SSB is transmitted according to inOneGroup. It is noted that the other indication information may be considered to be included in the first indication information, i.e. the first indication information includes two sub-indication information, first sub-indication information (e.g. inOneGroup, 8 bit bitmap) which is available when the maximum number of configurable SSBs in one SSB burst is less than or equal to Nssb, and second sub-indication information (e.g. groupPresence, 8 bit bitmap) which is available when the maximum number of configurable SSBs in one SSB burst is greater than Nssb, where Nssb is determined according to frequency band, e.g. 8. The UE may know the indexes (referred to as the second index group) of the transmitted SSBs (e.g., the SSBs finally transmitted by the base station) in an SSB burst based on the second indication information, which may be implemented in the manner of a bitmap (e.g., the implementation of the first indication information described above). From the first index group and the second index group, the UE may obtain a group of new SSB indexes, referred to as the third index group, where the third index group may be determined, for example, by selecting the indexes of the first index group that are not included in the second index group as the third index group. As an example, the second index group includes the indexes of {0, 2, 4, 6}, then the third index group includes the indexes of {1, 3, 5, 7}, and the UE may assume the SSB indexes indicated in the third index group as the indexes of the actually transmitted SSBs by the base station.

According to an embodiment, the second indication information indicates (e.g., directly indicates) the indexes of the transmitted SSBs in a second-type SSB burst. With continued reference to the specific example above, the second indication information may directly indicate the third index group. For example, in the above specific example, the second indication information may directly indicate the third index group as {1, 3, 5, 7}.

Optionally, the RO positions to which the corresponding SSBs in the third index group are mapped may be considered as new ROs for mapping the SSBs in a second-type SSB burst.

Optionally, the second indication information may indicate the indexes of the SSBs not actually transmitted in a first-type SSB burst, for example the indexes included in the above first index group are {0, 1, 2, 3, 4, 5, 6, 7}, where the indexes of the SSBs not actually transmitted are {0, 2, 4, 6}, then the second indication information may indicate the index group {0, 2, 4, 6}.

The above method indicates the SSBs actually transmitted in a first-type SSB burst by the additional second indication information, which does not affect the legacy user/UE (e.g., the user supporting only the first random access and not supporting the second random access, or receiving only the first random access configuration information and not receiving the second random access configuration information (second configuration information), such as users not supporting network energy saving) to select ROs. This is because the legacy user/UE (e.g., the user supporting only the first random access and not supporting the second random access, or receiving only the first random access configuration information and not receiving the second random access configuration information, such as users not supporting network energy saving) does not receive the SSBs indicated by the second indication information (e.g., the third index group), and thus the new ROs are unknown or unusable for these users.

Third Indication Information

The third indication information may indicate ROs associated with the first-type SSBs or the second-type SSBs, where the ROs are available to map the first-type SSBs or second-type SSBs.

Configuration Information Related to Time Domain Resources for Second-Type SSB Burst

The configuration information related to time domain resources for the second-type SSB burst may include at least one of (a) the transmission periodicity of the second-type SSB burst, (b) a time domain offset, (c) a number of second-type SSB bursts, (d) transmission indication information of the second-type SSB burst, (e) a transmission pattern of the second-type SSB burst, (f) a third transmission periodicity, or (g) a repetition period of the third transmission periodicity. Examples of the respective configuration information are described separately below.

(a) Transmission Periodicity of Second-type SSB Burst

Optionally, the transmission periodicity of the second-type SSB burst (e.g., T₂ as shown in FIG. 5) may be the same as the transmission periodicity of the first-type SSB burst (e. g. T₁ as shown in FIG 5.), i.e., T₁=T₂.

Optionally, it is satisfied that the transmission periodicity of the first-type SSB burst is an integer multiple (e.g., k1 times) of the transmission periodicity of the second-type SSB burst. Optionally, k1 is a power of 2, i.e., T₁ = k₁× T₂, where k₁=1,2,4,…,K₁. Here, the minimum of K1 is an integer of 1, i.e., for the case where T1 and T2 are the same, and the maximum of K1 depends on the value ranges of the transmission periodicity of the first-type SSB burst and the transmission periodicity of the second-type SSB burst. Specifically, when the transmission periodicity of the first-type SSB burst is configured as the maximum of its value range and the transmission periodicity of the second-type SSB burst is configured as the minimum of its value range, the maximum . For example, the value ranges of T₁ and T₂ may be the same, and both are {5ms, 10ms, 20ms, 40ms, 80ms, 160ms}, then the value range of K₁may be {1, 2, 4, 8, 16, 32}. The configuration may be applicable but not limited to a scenario where the probability that the UE performs random access based on the configuration information of the second-type SSB burst is greater than random access based on the configuration information of the first-type SSB burst. FIG. 6 illustrates an example in which the transmission periodicity of the first-type SSB burst is twice the transmission periodicity of the second-type SSB burst, i.e., T₁=2×T₂.

Optionally, it is satisfied that the transmission periodicity of the second-type SSB burst is an integer multiple (e.g., k2 times) of the transmission periodicity of the first-type SSB burst. Optionally, k2 is a power of 2, i.e., T₂ =k₂×T₁, where k₂=1,2,4,…, K₂. The minimum of K2 is an integer of 1, and the maximum of K2 depends on the value ranges of the transmission periodicity of the first-type SSB burst and the transmission periodicity of the second-type SSB burst. Specifically, when the transmission periodicity of the second-type SSB burst is configured as the maximum of its value range and the transmission periodicity of the first-type SSB burst is configured as the minimum of its value range, the maximum of

For example, when the values of T₁ and T₂ are in the same range of {5ms, 10ms, 20ms, 40ms, 80ms, 160ms}, the value range of K₂ may be {1, 2, 4, 8, 16, 32}; this configuration may be applicable but not limited to a scenario where the probability that the UE performs random access based on the configuration information of the first-type SSB burst is greater than random access based on the configuration information of the second-type SSB burst.

Optionally, the repetition period (T₄, as shown in FIG. 6) of the transmission periodicity of the second-type SSB burst may be less than or equal to the transmission periodicity of the first-type SSB burst; for example, when the transmission periodicity of the second-type SSB burst is less than the transmission periodicity of the first-type SSB burst, the UE may consider that the second-type SSB burst is repeatedly transmitted only within the transmission periodicity of the first-type SSB burst. For example, when the repetition period T₄ of the transmission periodicity of the second-type SSB burst is less than the transmission periodicity T1 of the first-type SSB burst in FIG. 6, the second-type SSB burst may be considered to be repeated only within T1 with a number of repetitions of two.

(b) Time Domain Offset

The UE may determine the time domain symbol starting position of the second-type SSB burst from the offset and a time domain reference point, where the unit of the offset may be at least one of a symbol, a slot, and a time interval; the time domain reference point may be a predefined or configured reference time (e.g., SFN = 0) or based on the symbol position where the first-type SSB burst starts or ends (e.g., as shown in FIG. 5 or 6).

Optionally, the time domain offset Tg may be (e.g., as shown in FIG. 7) based on the interval of the symbol position where the first-type SSB burst ends to the symbol position where the second-type SSB burst starts.

Optionally, the time domain offset Tg may be (e.g., as shown in FIG. 8) based on the interval of the symbol position where the first-type SSB burst starts to the symbol position where the second-type SSB burst starts.

An example is described below. For example, when the periodicity T₁ of the first-type SSB burst and the periodicity T₂ of the second-type SSB burst are both 80ms, and the duration periods of the first-type SSB burst and the second-type SSB burst are T₀= 5ms, taking the time of the starting symbol of the first-type SSB burst as the reference point (0 ms), the time of the candidate starting symbol of the second-type SSB burst may be {T₀, 2T₀, ..., (T₂/T₀-1)×T₀}, i.e., one of the set of {5ms, 10ms,..., 75ms}, the time of the #1 second-type SSB burst starting symbol shown in FIG. 5 is 5ms, i.e., the time domain offset of the #1 second-type SSB burst relative to the #1 first-type SSB burst starting symbol is 5ms within a time T1.

(c) Number of Second-type SSB Bursts

Through this configuration information, the UE may determine the number of the second-type SSB bursts included within a third transmission periodicity.

(d) Transmission Indication Information of Second-type SSB Bursts

Through this configuration information, the UE may determine the indexes of the second-type SSB bursts transmitted in a third transmission periodicity and/or the indexes of the second-type SSB bursts not transmitted. One possible implementation is that the transmission indication information of the second-type SSB bursts is a bitmap from which the UE may determine the indexes of the second-type SSB bursts. As a specific example, a bitmap may be {0, 1, 1, 1}, which corresponds, from left to right, to the second-type SSB bursts with indexes #0, #1, #2, and #3, from which the UE may determine, for example, that when 0 represents not configured and 1 represents configured, the second-type SSB burst with index 0 is not configured and the second-type SSB bursts with indexes 1, 2 and 3 are configured; or, when 1 represents not configured and 0 represents configured, the bitmap indicates that the second-type SSB burst with index 0 is configured and the second-type SSB bursts with index 1, 2 and 3 are not configured.

(e) SSB Pattern of Second-Type SSB Bursts

Through this SSB Pattern, the UE may determine the transmission pattern of the SSBs of the second-type SSB bursts in the time domain, e.g., the time domain distribution of the SSBs of the second-type SSB bursts within one slot (e.g., the first symbol index of the SSB in the second-type SSB burst). For example, the transmission pattern may be related to the subcarrier spacing of the second-type SSB. Optionally, the transmission pattern of the SSBs of the second-type SSB bursts may be the same as the transmission pattern of the SSBs of the first-type SSB bursts.

(f) Third Transmission Periodicity

The third transmission periodicity is configured for both the first-type SSB burst and the second-type SSB burst. For example, the third transmission periodicity may be an integer multiple of the transmission periodicity of the first-type SSB burst; optionally the multiple is a power of 2, and for example, when the transmission periodicity of the first-type SSB burst is 20ms, and the transmission periodicity of the second-type SSB burst is 10ms, the third transmission periodicity may be 20ms, 40ms, 80ms, etc. For another example, the third transmission periodicity may be an integer multiple of the transmission periodicity of the second-type SSB burst, optionally the multiple being a power of 2; for example, when the transmission periodicity of the second-type SSB burst is 10ms, and the transmission periodicity of the first-type SSB burst is 5ms, the third transmission periodicity may be 10ms, 20ms, 40ms, 80ms, etc. Optionally, the UE may consider that the number of transmissions of the first-type SSB burst is equal to 1 and the number of transmissions of the second-type SSB burst is greater than or equal to 1 within a third transmission periodicity.

(g) Repetition Period of Third Transmission Periodicity

The repetition period of the third transmission periodicity may be an integer multiple of the third transmission periodicity; optionally, the UE may consider that within a third transmission period, the time domain related configuration of the first-type and the second-type SSB bursts remains unchanged, e.g., the number of the first-type and the second-type SSB bursts, the periodicity of the first-type and/or the second-type SSB bursts, the time domain offset, the SSB pattern of the second-type SSB bursts, etc.

Configuration Information Related to Frequency Domain Resources for Second-Type SSB Bursts

Through this configuration information, the UE may know the starting position of the second-type SSB bursts in the frequency domain, the number of the second-type SSB bursts. Optionally, the configuration information may include a frequency domain resource offset, where the offset may be in a unit of at least one of a subcarrier, a subcarrier group, a PRB, a resource block group, a BWP, an/or the like. The UE may determine the frequency domain symbol starting position of the second-type SSB bursts from the offset and a frequency domain reference point, where the frequency domain reference point may be a predefined or configured reference PRB index or the position of the center frequency of the first-type SSB bursts.

TDD Configuration Pattern

Based on the configuration pattern, the UE may determine a time range including uplink and downlink transmissions, the number of slots occupied by the uplink and downlink, respectively, the number of consecutive downlink symbols after consecutive full downlink slots, the number of consecutive uplink symbols at the end of the slot before the full uplink slot, and/or the like. Optionally, the second TDD configuration pattern may be the same as or different from the TDD configuration pattern in the first random access configuration information. For example, the ratio of downlink transmissions to uplink transmissions in the second TDD configuration pattern may be greater than the ratio of downlink transmissions to uplink transmissions in the first TDD pattern configuration pattern.

Note that the SSB burst configured in the second information may be referred to as the second-type SSB burst (may also be referred to as a set of second-type SSBs, or a set of second downlink physical signals, where the set of second downlink physical signals includes one or more second downlink physical signals), where the second-type SSB burst may include one or more SSBs (in the example embodiments of the disclosure, the SSB in the second-type SSB burst may be referred to as the second-type SSB). For example, the first-type SSB burst may have a periodicity, and thus may be transmitted periodically. For example, the second-type SSB burst may have a periodicity, and thus may be transmitted periodically. If not otherwise indicated, the term "SSB burst" may refer to a first-type SSB burst and/or a second-type SSB burst, and the term "SSB" may refer to a first-type SSB and/or a second-type SSB. For example, the term "first-type SSB burst" may be replaced with "a set of first downlink physical signals", the term "second-type SSB burst" may be replaced with "a set of second downlink physical signals", the term "first-type SSB" may be replaced with "first downlink physical signal", and the term "second-type SSB" may be replaced with "second downlink physical signal".

For example, the second information may further include second random access related configuration information (which may be referred to as configuration information related to second random access, or configuration information for the second random access, or second configuration information in the example embodiments of the disclosure), which may include at least one of:

- a configuration index for random access (first random access configuration index), the random access configuration index indicating at least one of: a random access preamble format, a random access configuration period (second random access period), a number and position of random access frames in the random access configuration period, an index of a subframe or slot in a random access frame, a starting symbol position of the random access preamble in a subframe or slot, a number of random access slots in a random access subframe, a number of RO in one random access slot, a number of OFDM symbols occupied in an RO;

- a configuration index for a new random access (second random access configuration index), the second random access configuration index indicating configuration information related to random access resource period, and resource configuration related information, optionally the random access index indicating at least one of the following: a random access configuration period (third random access period), a number and position of random access frames in the random access configuration period, the indexes of subframes or slots in a random access frame, the starting symbol position of a random access preamble in a subframe or slot, a number of random access slots in a random access subframe, a number of ROs in a random access slot, a number of OFDM symbols occupied in an RO. Optionally, the configuration information indicated by the second random access configuration index is different from the random access configuration index indicated by the first random access configuration index indication and the random access configuration index included in the first random access configuration information; optionally, whether or not the second random access configuration index is used may be based on the configuration of the first random access configuration index or the random access configuration index included in the first random access configuration information, e.g., based on the second configuration information. When the first random access configuration is index n (e.g., n may be of a value from 0 to 255), the first random access configuration index is ignored, and the random access related configuration indicated by the second random access configuration index m is used, where the correspondence of n and m may be predetermined by protocols, e.g., in the form of a table; optionally, the second random access configuration index may indicate that at least one of the random access configurations indicated by the first random access configuration index or the random access configuration index included in the first random access configuration information uses another configuration, e.g., indicates that a random access configuration periodicity (e.g., configured as x = 16, y = 1, with a number of subframes as 1) uses another configuration (e.g., configured as x = 32, y = 1, with a number of subframes as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9), and the specific parameters of the configuration may be determined using a configuration table corresponding to the second random access configuration index. The benefit of introducing the second random access configuration index is that dense RO resources may be configured when the random access resource period is long, reducing the latency of random access;

- a mapping ratio (second ratio information) between SSBs to ROs for random access, where the mapping ratio is information related to a number of SSBs mapped to each RO; for example, a mapping ratio of 1 indicates that the ROs and the SSBs are 1 to 1 mapped (or associated); with a mapping ratio of 1/4, one SSB may be mapped to 4 SSBs. The mapping ratio may be for a single SSB, and the ratio of SSBs and ROs of may be the same or different for different SSB indexes; for example, SSB #1 may be mapped to 2 ROs, SSB #2 may be mapped to 4 ROs, SSB #3 may be mapped to 2 ROs. Optionally, the mapping ratio may be for a set of SSBs, where the set of SSBs includes multiple differently indexed SSBs; for example, a first set of SSBs includes SSBs with indexes of {0, 1, 2, 3}, and the mapping ratio between the set of SSBs to ROs is 1 to 2, i.e., one SSB is mapped to 2 ROs, and a second set of SSBs includes SSBs with indexes of {4, 5, 6, 7}, and the mapping ratio between the set of SSBs to ROs is 1 to 4, i.e., one SSB is mapped to 4 ROs. (The benefit of a non-uniform mapping ratio of SSBs to ROs is that by assigning non-uniform ROs to each SSB, a number of unused PRACH occasions may be increased, giving the base station the opportunity to enter sleep mode, saving energy consumption);

- a random access related period, including at least one of: a random access configuration period (second random access period), a mapping cycle of SSBs to ROs (second mapping cycle), an association period of SSBs to ROs (second association period), an association pattern period of SSBs to ROs (second association pattern period);

- a number of ROs in frequency domain for random access;

- frequency domain starting positions of ROs for random access, for example, the frequency domain starting position of the first RO, the other ROs in the frequency domain being deduced based on the position of the first RO and the size of the frequency domain resource occupied by one RO, and/or the frequency domain spacing of the ROs;

- a root sequence index of a random access preamble for random access;

- a number of random access preambles for random access, e.g., a number of preambles for the second random access on one RO;

- a power-related configuration for random access, including at least one of: a preamble target receive power for the second random access, a pathloss compensation coefficient alpha for the second random access (e.g. alpha×pathloss, when alpha is less than 1, indicating partial pathloss compensation; when alpha=1, indicating full pathloss compensation; when alpha>1, indicating excess pathloss compensation, which is beneficial to increase the UE's power when transmitting the preamble on the ROs associated with the second SSB, when using the normal preamble target receive power); a power delta value for the second random access, a power ramping priority and/or step for the second random access, etc.; when the UE uses the ROs associated with the second-type SSB for preamble transmission, the second-type SSB-specific power-related configuration described above is used; the transmit power P is determined based on one or more of the target receive power P0, "alpha×pathloss", delta, or "the power ramping step×the number of retransmissions".

For example, the ROs (the second-type ROs) determined based on the second configuration information may be used for mapping of the first-type SSB, may be used for mapping of the second-type SSB, or may be used for mapping of both the first-type and the second-type SSBs.

For example, the random access configuration information for the second random access shares the random access configuration information for the first random access or part of the random access configuration information for the first random access. For example, the random access configuration information for the second random access reuses the random access configuration information for the first random access, e.g., the random access configuration index for the second random access is the same as the random access configuration index in the random access configuration information for the first random access.

As an example, the random access configuration information for the second random access is all the same as the random access configuration information for the first random access.

As an example, the random access configuration information for the second random access is the same as the random access configuration information for the first random access with respect to the following contents: a configuration index; second ratio information; the number of frequency multiplexed ROs; the frequency domain starting position of the ROs; a root sequence index; the number of preambles; or a power-related configuration.

Note that the random access configuration information for the first random access may be referred to as first configuration information related to the first random access, and the random access configuration information for the second random access may be referred to as second configuration information related to the second random access, the second random access being related to the second feature, such as an NES or the like but not limited thereto, which is described with the NES as an example of the second feature for convenience of expression and easy understanding in the description herein. The random access configuration information for the second random access may also be referred to as new random access configuration information (or configuration information different from the existing random access configuration information), e.g., new NES random access configuration information may be obtained by configuration of the NES. The example embodiments of the disclosure in which NES random access configuration information is used to illustrate methods may be extended to other random access configuration information.

With continued reference to FIG. 4, in operation S420, it is determined whether the second-type RO is valid according to the above-described configuration information and/or a predefined method. For example, the validity thereof may be determined based on at least one of the following validity determination/determination methods,

In a validity determination method, the judgment/determination is performed on the second-type RO according to the existing validity rule described in the aforementioned first random access configuration information to obtain a valid RO, or a valid second-type RO (which may be expressed as a second-type valid RO).

In a validity determination method, an RO in a random access slot is a valid RO when the first symbol of the RO is at least N1 symbols after the last downlink symbol determined based on the second TDD pattern and/or the last SSB symbol.

In a validity determination method, an RO in a random access slot is a valid RO when the first symbol of the RO is at least N2 symbols after the last downlink symbol determined based on the second TDD pattern and/or the last SSB symbol and before the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol. For example, an RO is an invalid RO or an invalid second-type RO when a part or all of the symbols of the RO are located within N2 symbols after the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol.

In a validity determination method, an RO in a random access slot is a valid RO when the first symbol of the RO is at least N3 symbols after the last downlink symbol determined based on the second TDD pattern and/or the last SSB symbol and N4 symbols before the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol. For example, an RO is an invalid RO or an invalid second-type RO when a part or all of the symbols of the RO are located after N4 symbols before the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol.

In a validity determination method, an RO in a random access slot is a valid RO when the first symbol of the RO is at least N5 symbols after the last downlink symbol determined based on the second TDD pattern and/or the last SSB symbol and before N6 symbols after the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol. For example, an RO is an invalid RO or an invalid second-type RO when a part or all of the symbols of the RO are located after N6 symbols the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol.

In a validity determination method, an RO in a random access slot is a valid RO when the first symbol of the RO is at least N7 symbols after the last downlink symbol determined based on the second TDD pattern and/or the last SSB symbol and before N8 symbols after the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol. For example, an RO is an invalid RO or an invalid second-type RO when a part or all of the symbols of the RO are located before N8 symbols after the last downlink symbol determined based on the first TDD pattern and/or the last SSB symbol.

In a validity determination method, when an RO is not mapped to an SSB (or other downlink physical signal) within a certain time period, the RO is an invalid RO (referred to as a third RO); the range of the certain time period includes a mapping cycle, or an association period, or an association pattern period for first-type SSB-RO, a mapping cycle, or an association period, or an association pattern period for second-type SSB-RO, or a time unit (e.g., a slot), or a random access configuration period, or a configuration period for a TDD pattern, such as the first TDD pattern or the second TDD pattern.

In the above validity determination method, N1-N8 may be an integer equal to or greater than 0. The values of N1-N8 may be predetermined values or configured values. The values of N1-N8 may be the same or different.

Note that the SSB symbol referred to in the above validity determination method may be an SSB symbol of the first-type SSB or an SSB symbol of the second-type SSB. Further, one or more of the above-described validity determination methods may be combined in any suitable manner. A condition in a validity determination method may be combined with a condition in another validity determination method or other methods to form a new condition for judging validity.

With continued reference to FIG. 4, in operation S430, according to the configuration information and/or a predefined method, the mapping of SSBs to valid ROs may be determined using at least one of the following methods. Note that, for convenience, in describing the mapping of the first-type and/or second-type SSB to the first-type and/or second-type ROs below, unless otherwise specified, all ROs are valid ROs, where the first-type valid RO is a valid RO determined based on the first information and the second-type valid RO is a valid RO determined according to the method described in operation S420. In addition, the second-type invalid RO mentioned in the following method is the aforementioned third RO, that is, the remaining RO of the first-type valid RO that cannot map the entire SSB one or more times within an association period.

In a method, the configuration information related to the first-type SSB burst and the information related to SSB-RO mapping (included in first random access configuration information) are obtained according to the first information, where the configuration information related to the first-type SSB burst includes the first indication information, and the information related to SSB-RO mapping includes at least one of an SSB-RO mapping ratio (the first ratio information), an SSB-RO mapping cycle (the first mapping cycle), an SSB-RO association period (the first association period), and an SSB-RO association pattern period (the first association pattern period).

In a method, the configuration information related to the second-type SSB burst and the information related to second-type SSB-RO mapping (included in the second configuration information) are obtained from the second information, where the configuration information related to the second-type SSB burst includes at least one of the second indication information or the third indication information, and the information related to second-type SSB-RO mapping includes at least one of an SSB-RO mapping ratio (the second ratio information), an SSB-RO mapping cycle (the second mapping cycle), an SSB-RO association period (the second association period), and an SSB-RO association pattern period (the second association pattern period).

In a method, according to the obtained association pattern period of SSB-RO, SSB-RO mapping ratio and the valid ROs in the association pattern period of SSB-RO, SSBs are mapped to the valid ROs in the association pattern period of SSB-RO, where the SSB may be the first type SSB or the second type SSB.

For example, the method of mapping may include at least one of the following methods 1-a to 1-l.

In the method 1-a, the first-type SSBs are mapped to the first-type valid ROs in an association pattern period (first or second association pattern period) of SSB-RO according to the first or second ratio information; the second-type SSBs are mapped to the first-type invalid ROs. The mapping rule may be: first, mapping in ascending or descending order of preamble indexes within the first-type invalid ROs of a random access slot according to the indexes of the second-type SSBs, where the preamble may be the random access configuration index for the second random access (e.g., determined according to the root sequence index of the random access preamble and the number of random access preambles for the second random access); second, in the frequency domain, according to the indexes of the second-type SSBs, mapping to the frequency multiplexed first-type invalid ROs in ascending or descending order; third, in the time domain, mapping to the time multiplexed first-type invalid ROs within the random access slot according to the indexes of the second-type SSBs; and fourth, mapping to the first-type invalid ROs within the next random access slot according to the indexes of the second-type SSBs. FIG. 9 illustrates an example of SSB-RO mapping according to some example embodiments of the disclosure. As shown in FIG. 9, there are currently three first-type SSBs (SSB 0, SSB 1, SSB 2), two second-type SSBs (SSB 0, SSB 1), the first ratio information is 1:2, (i.e., one SSB is mapped to two ROs), and the second ratio information is 1:1 (i.e., one SSB is mapped to one RO); the first-type valid RO is RO 0 to RO 5, and the first-type invalid RO is RO 10 and RO 11; in the first type SSB-RO mapping, first type SSB 0 is mapped to RO 0 and RO 1, first type SSB 1 is mapped to RO 2 and RO 3, and first type SSB 2 is mapped to RO 4 and RO 5; in the second-type SSB-RO mapping, second-type SSB 0 is mapped to RO 10 and second-type SSB 1 is mapped to RO 11.

In the method 1-b, the first-type SSBs or the second-type SSBs are mapped to the first-type valid ROs corresponding to the third index group, and the rule may be the same as the rule for mapping to the first-type invalid ROs, and will not be repeated here. FIG. 10 illustrates an example of SSB-RO mapping according to some example embodiments of the disclosure. As illustrated in FIG. 10, there are currently three first-type SSBs (SSB 0, SSB 1, SSB 2), two second-type SSBs (SSB 0, SSB 1), the third index group is {2}, the first ratio information is 1:2, and the second ratio information is 1:1; the first-type valid ROs are RO 0 to RO 5, the first-type invalid ROs are RO 10 and RO 11; in the first type SSB-RO mapping, first type SSB 0 is mapped to RO 0 and RO 1, first type SSB 1 is mapped to RO 2 and RO 3, and first type SSB 2 is mapped to RO 4 and RO 5; in the second-type SSB-RO mapping, according to the third index group {2}, it is determined that the ROs to which first type SSB 2 is mapped are RO 4 and RO 5, second-type SSB 0 is mapped to RO 4, and second-type SSB 1 is mapped to RO 5.

Optionally, in the method 1-c, the second-type SSBs are mapped only to the second-type valid ROs, where the time-frequency resources of the second-type valid ROs are different from that of the first-type valid ROs.

FIG. 11A illustrates an example of SSB-RO mapping according to some example embodiments of the disclosure. Referring to FIG. 11A, there are currently two first-type SSBs (SSB 0, SSB 1), two second-type SSBs (SSB 0, SSB 1), the first ratio information is 1:2, and the second ratio information is 1:1; the first-type valid ROs are RO 0 to RO 3 and the second-type valid ROs are RO 4 and RO5; in the first-type SSB-RO mapping, first-type SSB 0 is mapped to RO 0 and RO 1, and first-type SSB 1 is mapped to RO 2 and RO 3; in the second-type SSB-RO mapping, second-type SSB 0 is mapped to RO 4 and second-type SSB 1 is mapped to RO 5.

Optionally, in the method 1-d, the first-type SSBs are mapped to the second-type valid ROs, where the time-frequency resources of the second-type valid ROs may be the same as or different from that of the first-type valid ROs. When the first-type SSB is mapped to the valid RO, it may be mapped to the first-type and the second-type valid ROs at the same time in a non-sequential order (the advantage of this approach is that the terminal may quickly discover the valid RO positions, reducing the delay of random access), or preferentially mapped to the first-type or the second-type valid RO (the advantage of this approach is that the probability of occurrence of random access collision may be reduced when the number of the first-type or the second-type RO is small). FIG. 11B illustrates an example of SSB-RO mapping according to some example embodiments of the disclosure. Referring to FIG. 11B, there are currently three first-type SSBs (SSB 0, SSB 1, SSB2), the first ratio information and the second ratio information are both 1:2, the first-type valid ROs are RO 0 to RO 3, and the second-type valid ROs are RO 4 and RO5; in the first-type SSB-RO mapping, first-type SSB 0 is mapped to RO 0 and RO 1, first-type SSB 1 is mapped to RO 2 and RO 3, and first-type SSB 2 is mapped to RO 4 and RO 5.

Optionally, according to the method 1-d, in the method 1-e, the first-type or the second-type SSB is mapped only to the second-type valid RO not overlapping with the first-type valid RO, where the time-frequency resources of the second-type valid RO and the first-type valid RO partially overlap. Here, the overlapped RO is expressed as the first/second-type valid RO. FIG. 12 illustrates an example of SSB-RO mapping according to some example embodiments of the disclosure. As illustrated in FIG. 12, there are currently two first-type SSBs (SSB 0, SSB 1), two second-type SSBs (SSB 0, SSB 1), the first ratio information is 1:2, and the second ratio information is 1:1; the first-type valid ROs are RO 0 and RO1, the second-type valid ROs are RO 4 and RO5, the first/second-type valid ROs are RO 2 and RO3; in the first-type SSB-RO mapping, first-type SSB 0 is mapped to RO 0 and RO 1, and first-type SSB 1 is mapped to RO 2 and RO 3; in the second-type SSB-RO mapping, second-type SSB 0 is mapped to RO 4, and second-type SSB 1 is mapped to RO 5.

Optionally, in the method 1-f, according to the methods 1-a and 1-b, the second-type SSB is simultaneously mapped to the first-type invalid RO and the first-type valid RO corresponding to the third index group, where the mapping order may be first mapped to the first-type invalid RO and then mapped to the first-type valid RO corresponding to the third index group; or first mapped to the first-type valid RO corresponding to the third index group and then to the first-type invalid RO.

Optionally, in the method 1-g, according to the method 1-a, 1-c, and/or 1-d, the second-type SSB is simultaneously mapped to the first-type invalid RO and the second-type valid RO, where the mapping order may be first mapped to the first-type invalid RO and then mapped to the second-type valid RO indicated by the third index group; or first mapped to the second-type valid RO and then to the first-type invalid RO.

Optionally, in the method 1-h, according to the methods 1-b and 1-c and/or 1-d and/or 1-e, the first-type and/or the second-type SSB is simultaneously mapped to the first type valid RO corresponding to the third index group and the second-type valid RO, where the mapping order may be first mapped to the first type valid RO corresponding to the third index group and then mapped to the second-type valid RO; or first mapped to the second-type valid RO, and then mapped to the first-type valid RO corresponding to the third index group and the second-type valid RO.

Optionally, in the method 1-i, according to the methods 1-a, 1-b, 1-c and 1-e, the second-type SSB is simultaneously mapped to the first-type valid RO corresponding to the third index group, the first-type invalid RO, and the second-type valid RO in non-sequential order; for example, it is first mapped to the second-type valid RO, then to the first-type invalid RO, and finally to the first-type valid RO corresponding to the third index group.

Optionally, in the method 1-j, the first type or the second-type SSB is mapped to the RO according to the RO indicated by the third indication information, where the third indication information indicates the RO with which the first type or the second-type SSB is associated.

Optionally, in the method 1-k, the indexes of the first type and the second-type ROs may be based on the total RO number and then sorted in a logical order. For example, in a case where there are three first type ROs and two second-type ROs, the indexes of the ROs may be {0, 1, 2, 3, 4}, where {0, 1, 2} corresponds to the first type ROs, {3, 4} corresponds to the second-type ROs; or, it is also possible to sort in logical order individually based on the number of respective ROs, for example, in a case where there are three first type ROs and two second-type ROs, the indexes of the first type ROs are {0, 1, 2} and the indexes of the second-type ROs are {0, 1}.

Optionally, in the method 1-1, there is no order between the first-type SSB-RO mapping and the second-type SSB-RO mapping. For example, the first-type SSB-RO mapping may be performed first, followed by the second-type SSB-RO mapping; or, the second-type SSB-RO mapping is performed before the first-type SSB-RO mapping is performed; or the first-type SSB-RO mapping and the second-type SSB-RO mapping are performed simultaneously.

Note that the above mapping pattern period may be replaced by a mapping period or a mapping cycle, or other time units, e.g. one or more slots; or, one or more random access configuration periods, and/or the like.

With continued reference to FIG. 4, in operation S440, the UE selects an RO and transmits a preamble (e.g., via PRACH) in the selected RO. For example, the UE may select a next-available RO from the above valid ROs based on the received first or second-type SSB, and the SSB-RO mapping (e.g., the RO may be randomly selected with equal probability when the SSB corresponds to consecutive ROs), and the UE transmits a preamble for random access in the selected RO; or, the UE is assigned an SSB and its mapped valid ROs, the UE selects the next-available RO from the ROs (e.g., when the SSB corresponds to consecutive ROs, the RO may be randomly selected with equal probability), the UE transmits a preamble on the selected RO for random access. Additionally or alternatively, the UE may receive a dedicated random access resource indication and transmit the random access preamble according to the received dedicated random access resource. The UE may obtain the UE-specific random access resource indication by at least one of a PDCCH order, a MAC control element (MAC CE), or RRC higher layer signaling.

In some implementation, the UE-specific random access resource indication may include at least one of the following: an SSB index, and/or an RO (first type RO and/or second-type RO) index to which the SSB index is mapped; an RO index indication; a dedicated preamble index; a dedicated RNTI indication; or a preamble transmission resource.

In some examples, the RO index to which the SSB index is mapped may include an index of the second-type RO to which the SSB is mapped (e.g., excluding the first type RO), or an index of the first type RO to which the SSB is mapped (e.g., excluding the second-type RO), or a common index of the second-type RO and the first type RO to which the SSB is mapped.

Additionally or alternatively, the index is obtained within a certain time period including a mapping cycle, or an association period, or an association pattern period for a first-type SSB-RO, a mapping cycle, or an association period, or an association pattern period for a second-type SSB-RO, or a time unit (e.g., a slot), or a random access configuration period, or a TDD pattern configuration period.

Additionally or alternatively, the RO index to which the SSB index is mapped may be one RO or multiple RO indexes, which may be an odd number or an even number of indexes.

In some examples, the RO index indication may include a second-type RO and/or a first type RO index within a time period.

The RO index may be a time domain separate index, or frequency domain separate index, or time-frequency two-dimensional joint index.

Additionally or alternatively, the RO index may include at least one of an index of a single RO, indexes of consecutive N ROs (N being a positive integer), an index of a first (e.g., starting) RO of the consecutive N Ros; the indexes of the subsequent N-l ROs of may be obtained in sequence.

Additionally or alternatively, the certain time period includes at least one of a random access related period or a TDD pattern configuration period. Here, the random access related period includes at least one of the following: a mapping cycle, an association period, or an association pattern period for a first-type SSB-RO, or a mapping cycle, an association period, or an association pattern period for a second-type SSB-RO, a time unit (e.g., a slot), or a random access configuration period.

For example, the dedicated preamble index includes a dedicated preamble index configured to the UE, which indicates the UE to select a preamble corresponding to the index for transmission.

For example, the dedicated RNTI indication includes an RNTI configured to the UE for use in searching/receiving feedback of the base station (e.g., PDCCH of feedback, etc.).

For example, the preamble transmission resource configuration (including time-frequency resource and/or preamble resource and/or transmit power-related configuration) may include at least one of:

- a time unit interval, e.g. an interval between a time unit in which the configured preamble transmission resource (e.g. RO in which the preamble is located) is located and a time unit in which the downlink resource indicated by the UE-specific random access resource is received; for example, based on the interval and the time unit in which the downlink resource indicated by the UE-specific random access resource is received, the time unit in which the preamble transmission resource is located may be determined.

- the starting symbol of an RO for preamble transmission in a time unit (e.g., slot) in which the preamble transmission resource is located, which may be indicated by an index value of the symbol in the time unit or by a number of symbol intervals between the starting symbol and the starting position of the time unit

- a number of time units and/or a number of frequency domain units occupied by an RO

- a format index of the random access preamble that indicates the format used by the configured preamble, the options of the format being predefined, where the number of time units and/or the number of frequency domain units occupied by the preamble format may be determined from each option.

- a root sequence index of the preamble

- a length of the preamble, e.g., 839 or 139, etc.

- a preamble subcarrier spacing

- the periodicity of the preamble transmission resource

- the content of the transmit power-related configuration may include at least one of the aforementioned second-type SSB-specific power-related configurations, which will not be described in detail herein.

The method according to an example embodiment of the disclosure described in combination with FIG. 4 may further include the UE receiving feedback information from the base station, specifically including at least one of the following: the UE detects feedback information using the first RNTI; the UE searches for the feedback of the base station in a designated control resource set (COREST) and/or search space; the UE searches for the feedback of the base station in the specified search window. For example, the feedback information may include at least one of a random access response (RAR), message 2, or message B.

In some implementation, the first RNTI includes at least one of the following:

- RA-RNTI calculated based on an RO used to transmit the preamble, e.g., according to the feature index and the feature group index. One possible implementation of calculating RA-RNTI is as follows: RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id+14 × 80 × k × 2×feature_id, where: k is the maximum value of f_id, e.g., k = 8; feature_id is derived for one or more features or feature group logical indexes configured for random access by the base station (e.g., the base station may configure feature_id separately for two features NES and message 3 repetition, with NES feature_id = 0 and message 3 repeat feature_id = 1).

- C-RNTI. For example, the UE receives the feedback of the base station using the C-RNTI configured by the base station.

- the aforementioned dedicated RNTI. For example, the UE receives the feedback from the base station by using the dedicated RNTI in the configuration of the configured random access resources by the base station.

In some implementation, the designated control resource set (COREST) and/or search space may be NES UE-specific (e.g., supported for use by NES UEs), or NES random access-specific (e.g., used by UEs transmitting using the second-type ROs).

In some implementation, the designated search window is NES UE-specific (e.g., supported for use by NES UEs), or NES random access-specific (e.g., used by UEs transmitting using the second-type ROs), specifically including the starting point and/or the length of the time unit if the search window, and/or the like.

FIG. 13 illustrates a flowchart of a method 1300 performed by a UE according to some embodiments of the disclosure.

Referring to FIG. 13, in operation S1310, the UE receives configuration information including first information related to a set of first downlink physical signals and second information related to a set of second downlink physical signals. For example, the details regarding the first information and the second information may refer to various implementation of the disclosure.

Next, in operation S1320, the terminal transmits a random access preamble based on one or more valid ROs, wherein the one or more valid ROs are determined based on the first information and the second information. For example, the details regarding determining one or more valid ROs based on the first information and the second information may refer to various implementation of the disclosure.

In some implementations, one or more of operations S1310 to S1320 may be performed based on the methods described according to various embodiments of the disclosure (e.g., the embodiments described in combination with FIGS. 3C-12).

In some implementations, the method 1300 may omit one or more of operations S1310 to S1320, or may include additional operations, for example, operations that may be performed by a UE as described according to various embodiments of the disclosure (e.g., embodiments described in combination with FIGS. 3C-12).

FIG. 14 illustrates a flowchart of a method 1400 performed by a base station according to some embodiments of the disclosure.

Referring to FIG. 14, in operation S1410, the base station transmits configuration information to the UE, where the configuration information includes first information related to a set of first downlink physical signals and second information related to a set of second downlink physical signals.

Next, in operation S1420, the base station receives a random access preamble based on one or more valid ROs, wherein the one or more valid ROs are determined based on the first information and the second information.

In some implementations, one or more of S1410 to operation S1420 may be performed based on the methods described according to various embodiments of the disclosure (e.g., the embodiments described in combination with FIGS. 3C-12).

In some implementations, the method 1400 may omit one or more of operations S1410 to S1420, or may include additional operations, for example, operations that may be performed by a implementation as described in accordance with various of the disclosure (e.g., embodiments described in combination with FIGS. 3C-12).

FIG. 15 illustrates a block diagram of a configuration of a first node (e.g., UE) as a scheduled node according to some example embodiments of the disclosure.

Referring to FIG. 15, the first node includes a transceiver 1510, a controller 1520, and a memory 1530. The controller 1520 may refer to a circuit, an application specific integrated circuit (ASIC), or at least one processor. The transceiver 1510, the controller 1520, and the memory 1530 are configured to perform the operations described above (e.g., described in combination with FIGS. 1-15) that may be performed by a terminal or UE. Although the transceiver 1510, the controller 1520, and the memory 1530 are shown as separate entities, they may be implemented as a single entity, such as a single chip. Alternatively, the transceiver 1510, the controller 1520, and the memory 1530 may be electrically connected or coupled to each other.

The transceiver 1510 may transmit and receive signals to and from other network entities (e.g., a base station).

The controller 1520 may control the first node to perform a function according to one of the various example embodiments described above.

In some example embodiments, the operations of the first node may be implemented using a memory 1530 storing respective program codes. Specifically, the first node may be equipped with a memory 1530 to store program code implementing desired operations. In order to perform desired operations, the controller 1520 may read and execute program codes stored in the memory 1530 by using at least one processor or central processing unit (CPU).

Referring to FIG. 16, the second node includes a transceiver 1610, a controller 1620, and a memory 1630. The controller 1620 may refer to a circuit, an application specific integrated circuit (ASIC), or at least one processor. The transceiver 1610, the controller 1620, and the memory 1630 are configured to perform the operations described above (e.g., described in combination with FIGS. 1-15) that may be performed by the base station. Although the transceiver 1610, the controller 1620, and the memory 1630 are shown as separate entities, they may be implemented as a single entity, such as a single chip. Alternatively, the transceiver 1610, the controller 1620, and the memory 1630 may be electrically connected or coupled to each other.

The transceiver 1610 may transmit and receive signals to and from other network entities (e.g., terminals).

The controller 1620 may control the second node to perform a function according to one of the various example embodiments described above.

In some example embodiments, the operations of the second node may be implemented using a memory 1630 storing respective program codes. In particular, the second node may be equipped with a memory 1630 to store program code implementing desired operations. In order to perform desired operations, the controller 1620 may read and execute program codes stored in the memory 1630 by using at least one processor or central processing unit (CPU).

Those skilled in the art will understand that the above illustrative embodiments are described herein and are not intended to be limiting. It should be understood that any two or more of the embodiments disclosed herein may be combined in any combination. Furthermore, other embodiments may be utilized and other changes may be made without departing from the spirit and scope of the subject matter presented herein. It will be readily understood that aspects of the invention of the disclosure as generally described herein and shown in the drawings may be arranged, replaced, combined, separated and designed in various different configurations, all of which are contemplated herein.

Those skilled in the art will understand that the various illustrative logic blocks, modules, circuits, and steps described in this application may be implemented as hardware, software, or a combination of both. To clearly illustrate this interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above in the form of their functional sets. Whether such function sets are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Technicians may implement the described function sets in different ways for each specific application, but such design decisions should not be interpreted as causing a departure from the scope of this application.

The various illustrative logic blocks, modules, and circuits described in this application may be implemented or performed by a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic devices, discrete gates or transistor logics, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors cooperating with a DSP core, or any other such configuration.

The steps of the method or algorithm described in this application may be embodied directly in hardware, in a software module executed by a processor, or in a combination thereof. The software module may reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor to enable the processor to read and write information from/to the storage medium. In an alternative, the storage medium may be integrated into the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a communication apparatus (e.g., a terminal or a base station). In an alternative, the processor and the storage medium may reside in a communication apparatus (e.g., a terminal or a base station) as discrete components.

In one or more exemplary designs, the functions may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, each function may be stored as one or more pieces of instructions or codes on a computer-readable medium or delivered through it. The computer-readable medium includes both a computer storage medium and a communication medium, the latter including any medium that facilitates the transfer of computer programs from one place to another. The storage medium may be any available medium that may be accessed by a general purpose or special purpose computer.

The above description is only an exemplary implementation of the present invention, and is not intended to limit the scope of protection of the present invention, which is determined by the appended claims.

Claims

A method performed by a user equipment (UE) in a wireless communication system, the method comprising:

receiving, from a base station, configuration information including first information associated with a set of first signals and second information associated with a set of second signals; and

transmitting, to the base station, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs),

wherein the one or more valid ROs are based on the first information and the second information.
The method of claim 1, wherein the configuration information further includes at least one of information indicating a number of the first signals mapped to one RO, and information indicating a number of the second signals mapped to one RO.
The method of claim 1, wherein the one or more valid ROs includes at least one of first valid ROs associated with a first random access, or second valid ROs associated with a second random access.
The method of claim 1, wherein transmitting the random access preamble comprises:

determining an available RO from the one or more valid ROs based on the first signals and the second signals; and

transmitting the random access preamble in the available RO.
A method performed by a base station in a wireless communication system, the method comprising:

transmitting, to a user equipment (UE), configuration information including first information associated with a set of first signals and second information associated with a set of second signals; and

receiving, from the UE, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs),

wherein the one or more valid ROs are based on the first information and the second information.
The method of claim 5, wherein the configuration information further includes at least one of information indicating a number of the first signals mapped to one RO, and information indicating a number of the second signals mapped to one RO.
The method of claim 5, wherein the one or more valid ROs includes at least one of first valid ROs associated with a first random access, or second valid ROs associated with a second random access.
The method of claim 5, wherein receiving the random access preamble comprises:

receiving the random access preamble in an available RO among the one or more valid ROs,

wherein the available RO is based on the first signals and the second signals.
A user equipment (UE) in a wireless communication system, the UE comprising:

a transceiver; and

a controller coupled with the transceiver and configured to:

receive, from a base station, configuration information including first information associated with a set of first signals and second information associated with a set of second signals, and

transmit, to the base station, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs),

wherein the one or more valid ROs are based on the first information and the second information.
The UE of claim 9, wherein the configuration information further includes at least one of information indicating a number of the first signals mapped to one RO, and information indicating a number of the second signals mapped to one RO.
The UE of claim 9, wherein the one or more valid ROs includes at least one of first valid ROs associated with a first random access, or second valid ROs associated with a second random access.
The UE of claim 9, wherein the controller is further configured to:

determine an available RO from the one or more valid ROs based on the first signals and the second signals, and

wherein the random access preamble is transmitted in the available RO.
A base station in a wireless communication system, the base station comprising:

a transceiver; and

a controller coupled with the transceiver and configured to:

transmit, to a user equipment (UE), configuration information including first information associated with a set of first signals and second information associated with a set of second signals, and

receive, from the UE, a random access preamble based on one or more valid random access channel (RACH) occasions (ROs),

wherein the one or more valid ROs are based on the first information and the second information.
The base station of claim 13, wherein the configuration information further includes at least one of information indicating a number of the first signals mapped to one RO, and information indicating a number of the second signals mapped to one RO.
The base station of claim 13, wherein the one or more valid ROs includes at least one of first valid ROs associated with a first random access, or second valid ROs associated with a second random access.